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I am doing the intake manifold gasket, valve cover gaskets and HEI distributor next. Is there any order that would be beneficial to do these in or it really doesn't matter?
I thought having the valve covers off first and back on last gives me more room for the manifold and makes being sure I am at TDC on the compression stroke for the HEI easier, but is getting the new distributor in while the manifold is off any easier?
IT doesn't matter the sequence to taking it apart. To me, I would do the intake, then VCs, then distributor. While the intake was off, I would pull each lifter and inspect the bottoms of the lifters and cam lobes and put them back in the same holes if they are all good. Its not a hard job because there are no adjustments associated other than tightening the rocker bridges.
Do you have the original intake manifold? Be aware it weighs ~45lbs. I'd remove the (1) distributor, (2) intake manifold & (3) valve covers. Toss an old heavy towel on top of the valve cover on the side of the engine you are going to lift & remove the intake manifold so you don't ding the valve cover and in case you need to set it down while removing it. One reason to leave the valve covers last is in case you accidentally happen to drop or bang the intake manifold against push rod covers, bridges, etc. When installing I'd install (1) intake manifold (2) valve covers & (3) distributor. I used the metal turkey tray intake manifold gasket (which is the OEM type gasket). There are two-piece intake manifold gaskets available if you so choose to go that route. Be aware you should always do a dry-run first in particular if you're using the metal turkey tray intake manifold gasket. There is a boss in each of the four corners of the metal turkey tray gasket which must fit into each indentation of the cylinder heads.
Last edited by Vintage Chief; May 11th, 2019 at 06:50 PM.
If you're replacing a contact points distributor w/ an HEI (even if you're not for that matter) and your vehicle is a running vehicle the distributor is most likely sitting @ TDC w/ the distributor #1 spark plug wire pointing to #1 cylinder. Before you remove the distributor cap, look at the #1 spark plug wire receptacle on the top of the distributor - it should be pointing to #1 cylinder. Mark (Score) a point on the distributor body (below) the distributor cover or wherever convenient (even on the firewall for that matter) and with a yard stick (or the like) make note that your mark/score is pointing to #1 cylinder and you'll know the orientation of the distributor to #1 cylinder. After you remove the distributor cover, note the orientation of your mark relative to the rotor - pointing to #1 cylinder.
Thanks for the tips guys. I wrestled the old manifold off, with carb attached as the Chiltons manual said. I expected it to have some weight but it was a little heavier then expected. I will be removing the carb to put back on, not only to lighten it a little, but more to give me a better place to hold and lower it back on. Also, looking at it now I will also remove the distributor before I put it back on. It looks like maneuvering around that could complicate things and since it is coming off soon anyway might as well do it now.
I took some pictures of the gasket before I removed it. To me, it looks like there was one fairly significant leak on the center of one side and one smaller leak on the center of the other side. Are these types of markings typical or am I correct to assume these were in fact leaks? The instructions with the new gasket, which appears to be exactly the same as the one that was in there, say to not only put RVT around the water ports, but also a little on the intakes on the side that connects to the head as well as the other side. There was RVT on the water ports, but none on either side of the intakes. I hopefully have found my vacuum leak.... now hopefully I can do a better job than the last guy.
The center port is an exhaust crossover, it heats the manifold under the carb to aid in warming up faster. What you see there is the effects of heat and condensation. You only need RTV around the coolant ports, the gasket has raised areas that basically crush seal between the head and the manifold as you torque it down. I usually grab a helper to seat the intake especially if you are using RTV in place of the rubber end seals.
Ah, I see. Well, hopefully this is still the cause of the leak somewhere. I don't know what else it could be. Either way, it is at least another thing to check off the list.
I reviewed a post you made elsewhere in another thread. I believe you stated you had 17" Hg? I believe the sbo in the CSM states the high side of the manifold vacuum is 17.5" so you shouldn't be tracing down a significant vacuum leak. I'll have a look at my CSM but pretty sure it states 17.5" Hg.
Whats it look like under the tray? Like I said above, now is a good time to inspect the lifters and cam. You probably already know, the tray gasket is only single use and needs to be replaced.
I haven't really dug to deep into anything under it yet. It was getting late by the time I got it off. Tomorrow will be clean up and further inspection.
If I recall, when I first used the vacuum gauge it read 11 or 12, and this was with the timing set to the stock numbers. After advancing the timing and playing with the fuel mixture, and replacing all the rubber tubing, and capping all open ports, including replacing one cap that I found to have a huge hole in, I got it up to just shy of 17" I think. It would be great if roughly 17" was good, but I everything I found said it should be 20 or better ideally.
A retired mechanic that I trust as well as a current professional both were positive it was running lean. We did a propane test all around the engine that made no difference so that lead to the belief that it might be an internal gasket leak. I will remain hopeful that the new gasket does the job and if not will start trying to figure out what else it could be... unless SBO do run around the 17" mark in which case maybe I am OK.
The mechanic had some equipment that showed the distributor to be very worn. I am looking forward to getting that replaced to see what kind of difference that makes too.
In 'general' we often employ the numbers 'between (generally) 17" Hg to 22" Hg for a V8 engine vacuum. This is not always the case for every single V8 engine. Certain devices you can control & these devices (type of distributor, model of distributor, vacuum model diaphragm, etc.) can influence vacuum. I'll let you be the judge. Here is the vacuum & mechanical advance for a stock Oldsmobile 350 CID from the 1971 CSM. Note the delta between a 350 CID & a 455 CID engine & the models of distributor & vacuum.
Thanks for posting that, it is very interesting and helpful. After all this is done and it is running again at least now if I am around the 17" mark at those timing numbers I won't be chasing numbers that are not realistic for this engine. Hopefully with all that has been done once it is timed and tuned right it won't be lean and everything will be good. I am excited but nervous at the same time about getting this fired up which should be in the next couple of days. I will be very happy if there isn't transmission fluid coming out anywhere, lol.
A helpful tool which has stood the test of time in diagnosing vacuum leaks has been the ability to read what the needle on a vacuum gauge can tell you. This information can be found anywhere on the internet. But here is a decent link for you to view reading a vacuum gauge.
Here is a paper model/image you could print out if you so choose. Again, this information can be found anywhere on the internet. I ripped this image from Post #2 by jaunty75
That chart will come in handy as soon as I get it going.
Before I can do much more than the clean up, I first have to get the bolts out on the thermostat housing that snapped off yesterday. I was hopeful that soaking them with Kroil and welding some nuts on the nubs sticking out of the manifold would work but no luck there. I guess my only options now are to try to drill them out or replace the manifold. If drilling them out, would it be better to try to drill the bulk of the bolt out, and run a tap through trying to save the original threads, or drill the whole thing out and use a heli-coil?
Me - I'd first attempt to center drill the bolt & use an easy out. Cover everything up w/ towels, rags, etc. When you have your center drill hole made, as you insert the easy out, use a (preferably) small finishing hammer to lightly but 'firmly' tap (set) the easy out into place. Use a pair of vice grips (my preference) clamped securely to the easy out for turning CCW and while tapping. As you begin turning the easy out CCW, continue to place slight/light but secure 'taps' on the easy out - continuing to turn CCW. Be 'patient' - don't rush it - be methodical about it. Make the center drill hole ~1/3 diameter of the bolt. You can/should begin to 'feel' the easy out begin to produce a slight flex in the shaft of the easy out. Get a sense for the 'feel' of the easy out shaft flexing. If you feel the easy out is too small - go one larger. But do continue w/ the slight but firm taps as you turn CCW.
Last edited by Vintage Chief; May 13th, 2019 at 03:49 PM.
Thanks, that is a good idea. I will head out tomorrow morning to pick up a set of those. It looks like the bolt holes go right through to the other side so now that the carb is off I am going to flip it upside down and try to spray some of that Kroil stuff in there and hopefully have it soak in over night to help this work. The reviews on the tools were mixed, but that probably goes back to what you were saying about being slow and careful and having patience.
Personally, I get better penetration for my money using Transmission fluid as a penetrating oil or Liquid Wrench. Kroil, IMO, does less than a fair job as a penetrating fluid and for the price of it, I'd rank it towards the bottom of my list. I'd use PB Blaster before I'd use Kroil. JS
EDIT: I always have some Acetone on hand for many things around the ponderosa. I often mix some acetone with transmission fluid (50:50), shake it real good because it separates like oil & vinegar. You don't need tons of either transmission fluid or the mix I mentioned - you need ONLY enough to cover the bolt - which should equate to about one teaspoon.
Last edited by Vintage Chief; May 13th, 2019 at 04:47 PM.
Well, I did my best but had no success. I was at it for a while and felt the flex/twist of the easy out. It felt like it would break very easily so I worked at it for awhile being as careful as I could. I guess being my first time using these and not knowing exactly what to expect I pushed a little too hard and it eventually snapped off. For how severely corroded they are I really doubt anything was going to get them out.
Now the issue is that the drill bit doesn't seem to be able to drill into the broken off piece of the tool, so attempting to drill them out is probably off the table, which I think really leaves replacing the manifold as my only option.
So, on that note, for a basically bone stock car that is likely going to stay that way, is there any after market manifolds that are stock replacements or close to stock with some small improvements that are worth doing? I checked OPGI, Supercarsunlimited, rockauto, summit and jegs and of the sites that had them, it seems like the Edelbrock performer series is as close to stock as it is going to get. I just don't want to inadvertently upgrade or change something that won't work well with the otherwise stock setup. Also, is there a difference between a chevy intake and oldsmobile?
I am going to try and figure out another solution to save the old one, but I don't think that is going to be possible.
Well, I did my best but had no success. I was at it for a while and felt the flex/twist of the easy out. It felt like it would break very easily so I worked at it for awhile being as careful as I could. I guess being my first time using these and not knowing exactly what to expect I pushed a little too hard and it eventually snapped off. For how severely corroded they are I really doubt anything was going to get them out.
Now the issue is that the drill bit doesn't seem to be able to drill into the broken off piece of the tool, so attempting to drill them out is probably off the table, which I think really leaves replacing the manifold as my only option.
So, on that note, for a basically bone stock car that is likely going to stay that way, is there any after market manifolds that are stock replacements or close to stock with some small improvements that are worth doing? I checked OPGI, Supercarsunlimited, rockauto, summit and jegs and of the sites that had them, it seems like the Edelbrock performer series is as close to stock as it is going to get. I just don't want to inadvertently upgrade or change something that won't work well with the otherwise stock setup. Also, is there a difference between a chevy intake and oldsmobile?
I am going to try and figure out another solution to save the old one, but I don't think that is going to be possible.
Thanks guys
I'll tell you this. I (as many) have been in your exact same position - a broken easy out now occupying your cavity. It looks completely impossible right. There is still hope for the best. You'll probably go through a couple more drill bits (possibly), but grab a very sharp large drill bit. Do your best to remain in the confines of the bolt hole threads if at all possible to save the threads. Then, drill another large hole right next to the broken easy out. The drill will most likely heat up the busted easy out in the hole, cracking the easy out, and then you can continue drilling a large hole and using a much larger easy out and try again. Seriously, try again - drill that sucker out, bang in a larger easy out and give it a seriously hard time! Bang that easy out, crack that FU()ING bolt then grab it with the easy out and yank it out. Far better to keep the threads if possible than to now go chasing down an intake manifold. Go for it. The other bet is to use some heat from a propane torch directed towards the bolt then try the easy out after drilling a new hole. I'd rather drill out the entire hole, ream & clean it with chasers then insert a helicoil if the easy out fails before chasing down an intake manifold - but that's me. You can make numerous small drill holes on all sides of that broken easy out. Make about 3-4 small drill holes surrounding the easy out and see if that easy out doesn't finally give way.
Last edited by Vintage Chief; May 14th, 2019 at 10:25 AM.
Awesome, thanks for the advice. I will get back to work on it. Worst thing that can happen is that I completely butcher it and then have to go find a new one anyway, but there is a chance I can save this thing at least. Good thing there are no kids in the house, I think the language is about to get very aggressive, lol
Awesome, thanks for the advice. I will get back to work on it. Worst thing that can happen is that I completely butcher it and then have to go find a new one anyway, but there is a chance I can save this thing at least. Good thing there are no kids in the house, I think the language is about to get very aggressive, lol
Understand entirely. Unfortunately, it does happen sometimes. There is no issue with drilling sideways into those bolts - anything to grab them with the easy out - doing the best you can to remain inside the threads. Good luck!
Alright, it took just about every small drill bit I had through breaking them and constantly sharpening the few that didn't break, but it is done. I was making good progress on one side of the broken EZ out, but then the drill bit snapped off flush so now I had two pieces that couldn't really be drilled through. So I moved to the other side and through a lot of drilling, hammering on punches and profanity I finally managed to get it all out. There was no saving the original threads, but the heli-coil went in nice and is all fixed. On the other side I just went ahead and drilled it out and did the heli-coil. I didn't want to risk breaking off anything in there and making a short job into a long one on that side too.
Thanks for all the help and suggestions. I am very happy to have saved the original manifold and not had to go spend money on a new one.
Alright, it took just about every small drill bit I had through breaking them and constantly sharpening the few that didn't break, but it is done. I was making good progress on one side of the broken EZ out, but then the drill bit snapped off flush so now I had two pieces that couldn't really be drilled through. So I moved to the other side and through a lot of drilling, hammering on punches and profanity I finally managed to get it all out. There was no saving the original threads, but the heli-coil went in nice and is all fixed. On the other side I just went ahead and drilled it out and did the heli-coil. I didn't want to risk breaking off anything in there and making a short job into a long one on that side too.
Thanks for all the help and suggestions. I am very happy to have saved the original manifold and not had to go spend money on a new one.
Good deal. Just a single question to ensure you completed it correctly (which I'm sure you did but never hurts to ask before you thread your bolts into place when installing the thermostat housing).
You did break off the tab at the ends of each helicoil? And, you accounted for the tab piece(s) by extracting them w/ a magnet or some method.
I did remember to snap them off. That would be frustrating to forget and not notice until the bolts are going back in. And by then I don't know if I would even notice and they would just be loose in the system which probably isn't good. The manifold is off the car so it was easy to just get the out through the ports. After I get the surfaces all cleaned up I am going to blow it out really good with compressed air. Should I be worried about the Kroil residue that is left in there mixing with the coolant and causing issues? Seems like it would be such a small amount that it wouldn't matter.
After I get the surfaces all cleaned up I am going to blow it out really good with compressed air. Should I be worried about the Kroil residue that is left in there mixing with the coolant and causing issues? Seems like it would be such a small amount that it wouldn't matter.
(1) Determine if you're going to paint your intake manifold since now provides you the best opportunity. When I cleaned my intake manifold (mine was filthy) I soaked it w/ Easy Off Oven Cleaner ~10 minutes, did some light scrubbing with a brush in the bad areas, then pressure washed the entire intake manifold. I allowed it to set in the sun to dry, then I blew it out completely w/ compressed air & painted it;
(2) Don't worry about any Kroil residue.
So my most hated part is done - the cleanup. It is hard trying to keep something in there to catch as much of the crap from falling in as possible while you sand all the old stuff of down to clean metal. But, it is done and my back is now giving me the finger.
I did a test fit with the new gasket. The rubber pieces fit and I don't see any issues there. But the metal gasket it self I can see being a fun time unless that RVT does a better job at holding it down that I think it will. There is those pieces that snap in at the four corners which is great, but I couldn't seem to get all four to stay in at the same time. Every time I tried getting the last one in one or two of the others popped out. That should be fun when there is no time to waste, the RVT is setting as I am trying to lower the manifold back on and the thing won't stay in. Even with a couple other people I don't know if there would be enough room to keep it pushed down while the manifold goes in without crushing some fingers.
I will get back at it tomorrow. Perhaps some slight bends to the gasket will get it to sit in there better on it's own.
You are using the metal turkey tray gasket like the OEM turkey tray gasket. Be aware there were & have been some issues with some of the boss indents fitting the holes correctly. Mine was such the case and the reason I suggested you perform a dry-run w/o gasket seal first. I had to essentially flatten out two of the boss indents so they were flat & then create (with a punch) much, much smaller holes in the two I flattened so the gasket would fit correctly. Notice on the driver's-side (LH-side) there is one intake manifold hole which is not a hole but instead a rectangle. This is there on purpose as it was used as a 'guide' during the assembly so a line worker could quickly throw the intake manifold on top the cylinder heads as the vehicle rolled down the assembly line. What you can do is take a long bolt of the same type or a piece of steel using it as a dowel rod for a guide - long enough to protrude above the intake manifold so you can just remove it when you have the intake manifold in-place. Whichever the case, consider putting a bolt or dowel rod in that hole so you can quickly find the point where the intake manifold fits.
Some don't use the rubber end-pieces, as they use RTV (BTW, it's not RVT), instead on each end where the rubber end pieces are in-place. Whichever is the case for you in terms of how you assemble your rubber end pieces, be sure to put an extra glob at each corner of the ends of the rubber pieces where they meet the intake manifold. Torque to specifications - don't over torque the intake manifold and torque in sequence as per the CSM.
That is frustrating when a piece needs modifications like that to work. I had some issues with the last round of gaskets I tried for the valve covers. They were the thick rubber kind, but they didn't quite fit the bolt holes and still leaked after. I am going with cork this time. Hopefully they fit properly and if they need slight modifications cork will be a lot easier that that thick rubber.
Thanks for the tip on the notched hole on the manifold. I am going to run out tomorrow and get a bolt to use as a guide. That will take the trouble out of trying to make sure it is lined up. I went and made a few slight bends and it actually looks like it sits well now with all the corners snapped in. Luckily for me those punched out corners fit and snap into place, just needed some help to have them all sit in at the same time and didn't need and modification that yours did.
I also found that using the longer carb bolts on the back two holes with the bracket that the throttle cable mounted to makes a nice handle on the manifold. I feel a lot better about getting this finished up tomorrow now. Other than the manifold being a heavy bastard and awkward to lower in while bent over the fender of a car, I think I have made it as easy as I can.
Maybe I had a bad set or a bad brand. I can't recall exactly what they were, but am sure they were from Rockauto. I already bought the cork so I will give it a shot. Luckily these are easy enough to change if they still leak.
Any opinions on either anti-seize or loc tite thread sealer for the thermostat housing bolts? Seems to be arguments for and against online, just wondering if anyone had some first hand experience on these engines. I just want to make sure coolant won't wick it's way up the bolts and leak, and definitely don't want them to get corroded in place and break off again next time the thermostat needs changing.
Last edited by 71OldsCut; May 15th, 2019 at 10:02 PM.
I am close to done, but now with the larger HEI in place, the air cleaner no longer fits. A local shop has a 14" aftermarket air cleaner and spacer they say will work. I was going to just add a breather on the passenger valve cover to replace the connection to the old air cleaner but have read that you shouldn't mix PCV valves and breathers. Since I have a PCV on the drivers side that goes to the carb, what should I do? Would two breathers be better for vacuum than plugging the passenger side valve cover and keeping the PCV as is? Any other pros/cons to either setup?
I never thought about how the larger HEI would hinder the air cleaner placement. I don't run an HEI so I can't comment on the mixing of PCV valves & breather types. Plenty of users here who do. I'm sure someone will jump in w/ some advice.
I don't understand the concern of mixing PCV and breathers? You need one of each. a PCV on one VC, and a breather on the other. The PCV through a manifold vacuum port draws air out of the block, the breather allow fresh to enter the opposite side.
The guy at the local performance parts store thought the same. The only reasoning I could find is on newer cars with MAF sensors and computers. Should be fine on this car I think.
I don't know what could have went wrong, but the car won't turn over now, starter won't engage at all. When I hooked the battery back up I thought it might just be a bad battery. It read 11.8V. Apparently anything 12V or less is considered dead. Since it was the incorrect side post battery I figured I would just get a new one to rule that out. No change. So, I got back under it to check it. I thought maybe I left a connection loose or something.
I know when I took it off, I put electrical tape on one of the terminals and its corresponding wire so I knew what went where when reinstalling. In case I somehow still messed this up, what would happen if the two small wires were in the wrong spots? What are the two small wires for anyway?
Other than that, I thought maybe a fuse, but there doesn't seem to be a fuse for the starter.
Any ideas? I was very careful not to drop it or bang in into anything when taking it off and putting it back on. It just seems strange that it worked fine before and seems locked up now. As far as I know nothing involved in the HEI install would have caused anything like this.... so close yet so far, lol.
Your battery voltage at full charge should be 12.6v (the .6 is very important). 12.06 is 50% and anything below that the car may not crank over. Do the headlights work, and if on while trying to start do they go dim or out? I don't know what little wires your talking about, pictures?
First thing this morning I went and got a new battery. I figured with it being the incorrect side post type as well as being below 12V it was probably a good idea whether it was the cause or not, so nice new strong top post battery in there now.
There are three wires to the starter - one is the large one directly from the battery and then there are two small wires, maybe 16-18 gauge? that also connect. I see there is a way to test them but the article was unclear and my electrical knowledge is not great. It said to put one lead of a multimeter to the connection and the other to ground, but said nothing about if someone should be trying to turn the car over, or just with the key off, or in the run position. I was also unclear about what the dial on the multimeter should be set to and what type of read out I would be looking for.
The parts store near by still tests starters so I may just run it down to them tomorrow to confirm the starter is good or not and go from there. If it is good, then I guess one of the wires must be bad somewhere.
May 11th, 2019, 06:28 PM
