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So, l've had a timing chain failure in the 403 in my Buick wagon. Have searched and found enough threads to totally scare the bjeezus out of me and am pretty confused at the moment. Is there a detailed thread on the subject for 403's?
I have not opened it up yet and have a few questions before I do.
Are the cam gear teeth or any part of the gears nylon which would cause concern that bits of plastic have contaminated the oil.
If the answer to the above is no nylon/plastic parts requiring cleaning of the oil pan and filter, is it necessary to remove the oil pan or can just the front end of the pan be dropped to allow removal/replacement of the chain cover.
If I elect to remove oil pan, is there a better gasket to consider using.
Any tips on doing this will be greatly appreciated.
You are going to be way ahead if you just pull the engine. You can change it in the car, but you have to remove so many things, and it is a pain to do so.
Sorry Joe. it wasn't my intention to cross post, I had posted there earlier as it brought up a lot of questions, but that was before deciding to post here. For sake of continuity I've posted your response to that one here. Again, sorry...
Originally Posted by MrEarl
Bringing this old thread back up to ask if the '79 403's still had these nylon teeth and can I expect to find a similar situation in my 79 Buick wagons 403 when I change out the timing gear set. Seeing this suggests that the pan needs to be dropped not only for ease of reinstalling the timing chain cover but also to allow the oil pan and pump to be cleaned. Correct?
Thanks
Edit) oops, seeing now this isn't a 403 engine thread. I've been searching for info re swapping timing chains and this one came up. May still be applicable though???
Originally Posted by Joe Padavano >
Ever Olds V8 from 1964-1990 came with the plastic teeth on the cam gear. If there's an all-metal gear in there, it didn't come from the factory. Yeah, the pan wants to be dropped, but you pretty much have to pull the motor to do that. Trying to pull the pan with the engine in the car is painful and you're only six bellhousing bolts away from pulling the motor anyway. I've done a lot of these without pulling the pan. Change the gear before 80K miles and the amount of plastic fragments in the pan is usually pretty small.
Mr. Earl, that's a bummer that your 403 needs a timing chain. Go ahead and pull the engine like the others said. It will make installing the oil pan and timing chain cover easier. You don't have to worry about the deteriorated plastic timing gear teeth in the oil pan, they come apart but don't disintegrate. It should be an easy clean up.
You are going to be way ahead if you just pull the engine. You can change it in the car, but you have to remove so many things, and it is a pain to do so.
Originally Posted by MrEarl
Sorry Joe. it wasn't my intention to cross post, I had posted there earlier as it brought up a lot of questions, but that was before deciding to post here. For sake of continuity I've posted your response to that one here. Again, sorry...
Originally Posted by MrEarl
Bringing this old thread back up to ask if the '79 403's still had these nylon teeth and can I expect to find a similar situation in my 79 Buick wagons 403 when I change out the timing gear set. Seeing this suggests that the pan needs to be dropped not only for ease of reinstalling the timing chain cover but also to allow the oil pan and pump to be cleaned. Correct?
Thanks
Edit) oops, seeing now this isn't a 403 engine thread. I've been searching for info re swapping timing chains and this one came up. May still be applicable though???
Originally Posted by Joe Padavano >
Ever Olds V8 from 1964-1990 came with the plastic teeth on the cam gear. If there's an all-metal gear in there, it didn't come from the factory. Yeah, the pan wants to be dropped, but you pretty much have to pull the motor to do that. Trying to pull the pan with the engine in the car is painful and you're only six bellhousing bolts away from pulling the motor anyway. I've done a lot of these without pulling the pan. Change the gear before 80K miles and the amount of plastic fragments in the pan is usually pretty small.
OK, based on the responses so far...
The engine has 137K miles. I have all mechanical work receipts from when the car was new and not seeing any related to timing chain replacement. Two heads replace yea.
I am not set up space and tool wise right now to pull the engine. The shop where I had it towed when it failed on the road and that does my general repair work doesn't "pull engines", just their policy.
Originally Posted by Olds64
Mr. Earl, that's a bummer that your 403 needs a timing chain. Go ahead and pull the engine like the others said. It will make installing the oil pan and timing chain cover easier. You don't have to worry about the deteriorated plastic timing gear teeth in the oil pan, they come apart but don't disintegrate. It should be an easy clean up.
Bummer indeed but serves me right, I knew the car was over due for a timing chain change out. It's been one step forward, two back since I've had this car. Some due to my own ignorance some due to trying too hard and literal overkill creating more problems than necessary. I've JUST gotten the carb problems straightened out and she was running like I never knew she could.
Will be talking to the shop today and advising of what I learned here and see what they have to say.
I did my timing chain last year...engine in car and oil pan tightly bolted to engine. It can be done, but it's a PITA. Next time I'll just pull the engine and git'er dun.
I did my timing chain last year...engine in car and oil pan tightly bolted to engine. It can be done, but it's a PITA. Next time I'll just pull the engine and git'er dun.
The shop where I had it towed when it failed on the road and that does my general repair work doesn't "pull engines", just their policy.
If that's the case then if they offer a guarantee that there won't be any leaks from the timing chain cover or oil pan after replacing the timing chain then go for it. Otherwise, maybe they can refer you to a different shop.
If the engine had good oil pressure prior it will have the same oil pressure after the change is done. Its not a requirement to drop the pan, its just a recommendation, a lot of us have just done it in the car, performed an oil change at the end and pressed on with no ill effects.
So spoke with the shop today and expressed my concern re the possibility of the nylon sprocket pieces blocking the oil pump screen. He understood and said he would try to lift the engine enough to remove the pan and clean the sump and screen. I feel good that he will follow through and if necessary pull the engine. I explained to him that I do not want go through all this work, get the engine back together then be faced with leaking gaskets or worse still, low oil pressure from a restricted pump screen. He knows what I have been through with this car and I think will ensure that doesn't happen.
I asked this in another thread with not much response so while I have your attention...
I have read about using a "diesel" type oil pan gasket. Can someone point me in the right direction for that. When googling, I come up with this https://www.summitracing.com/parts/fel-os30471c is this correct?
Any recommendations for a timing gear and chain set. Standard or double roller. Any recommended manufacturer Gasket ?
Earl, let your mechanic recommend a timing set. Single vs. double roller on a street driven car won't make a difference. Your mechanic can probably get a good price on an OE single roller timing set.
Personally, I use FelPro TCS45270, which includes the repair sleeve for the balancer where it gets worn from the seal.
If you are looking for a replacement timing set, Sealed Power CTS 1005 has the timing set (with metal cam gear) and a FelPro gasket set (though without the sleeve) for $24 at RockAuto. You can buy the sleeve separately.
If the water pump, belts, hoses, radiator and or fuel pump are old they could be replaced inexpensively as they will need to be removed as part of the timing chain labor.
If the water pump, belts, hoses, radiator and or fuel pump are old they could be replaced inexpensively as they will need to be removed as part of the timing chain labor.
Good luck!!!
That's how I MIGHTASWELL myself into a complete engine rebuild...
Thanks for all your suggestions. While they were coming in I was still Google searching this forum for past related threads trying to learn more and to see what others had used. Here is some of what I came up with are currently available for pick up at Summit. I can run over to Summit Monday and pick up (curbside pickup)
May or may not go with this ProComp double roller, looks like a good price for a double roller and allows advance/retard adjustment (if that is of any great benefit ) Has anybody used one?
I kept seeing posts referencing a ONE PIERCE 350 Diesel oil pan gasket that reportedly worked but could not find one available on line. Did also read good comments on this FelPro set. Thoughts?
As a Might as Well if the mechanic is willing while he has the engine lifted and oil pan off I'd like to replace the rear main seal. Someone here recommended going with a "Ford" rear main seal. This is what I found , is this correct? https://www.summitracing.com/ga/part...bs6141/reviews
I would like to get this stuff ordered and go pick up on Monday and to the shop. THANKS everyone for your time and help!!!
There is no such thing as a one-piece oil pan gasket for an Olds motor. The diesel gasket is a cork laminate with a steel core, unlike the all-cork gaskets normally used. As for the timing set, unless you plan to go through the trouble to degree-in the cam, I'm not sure what an adjustable timing set will do for you, except cost more. Let's be honest here, a B-body wagon with an otherwise stock 403 is still not a drag car. Your money, your call. Yes, the Y-block rear main seal is the correct one. Just discard the two straight seals that are not used for an Olds.
If the water pump, belts, hoses, radiator and or fuel pump are old they could be replaced inexpensively as they will need to be removed as part of the timing chain labor.
Good luck!!!
Originally Posted by joe_padavano
That's how I MIGHTASWELL myself into a complete engine rebuild...
I am very embarrassed to say this but I've spent the last month installing all of what Sugar Bear mentioned above, knowing dang well I should be changing out the timing chain but with knowing the difficulty factor involved elected to take my chances awhile longer. A decision I am SOOOO regretting now. But on the positive side, the three row aluminum radiator, FlowCooler water pump and FlowCooler 180 thermostat brought the operating temperature down from 205-210 to 170-175. I'm sure that will increase when towing in the summer months but should help tremendously. While in there, I also mounted two transmission coolers onto the radiator cross member, about 6 inches in front of the radiator.
There is no such thing as a one-piece oil pan gasket for an Olds motor. The diesel gasket is a cork laminate with a steel core, unlike the all-cork gaskets normally used. As for the timing set, unless you plan to go through the trouble to degree-in the cam, I'm not sure what an adjustable timing set will do for you, except cost more. Let's be honest here, a B-body wagon with an otherwise stock 403 is still not a drag car. Your money, your call. Yes, the Y-block rear main seal is the correct one. Just discard the two straight seals that are not used for an Olds.
FYI, the RockAuto price is less than half that of Summit.
Yea, I know and I typically shop Rock Auto but want to have these parts to the shop the "first of the week" . You feel good with the Cloyes gears and chain?
Yea, I know and I typically shop Rock Auto but want to have these parts to the shop the "first of the week" . You feel good with the Cloyes gears and chain?
So, I've found a highly recommended shop about an hour from me and will be loading the car on my trailer and delivering to them this week. They will be pulling the engine to replace the timing chain, clean the oil pump screen and replace the rear main seal. Considering the engine has 137K miles on it, my "might as well" questions now are
Should I replace the oil pump or just clean and reinstall the current one. If replace, looking at Melling pump and pick up with screen $91 at Rock Auto. Good?
Is there ANYTHING else within reason that I should consider having done while the engine is out?
Is there ANYTHING else within reason that I should consider having done while the engine is out?
Melling M22HV is what I usually use. The stock pump is fine, I just like the high volume pump for a little added insurance. And no, it will NOT "suck the pan dry".
The MIGHTASWELLS add up in a hurry. With the pan off, you MIGHTASWELL check the bearings. Of course, if you are going to pull the main and rod caps, you MIGHTASWELL just put in new ones. Definitely go with a neoprene rear main seal. I'd probably replace all the steel freeze plugs with brass while it's out. Of course, at 137K, it probably wants valve seals too...
You begin to understand how this gets to a full engine rebuild pretty quickly.
Ask the shop if they will install the chain and gears then STOP putting it back together and do either a compression test or a leakdown test. This is to avoid putting it back together and installing it to find it doesn't run properly due to low compression on certain cylinders. If it tests good, carry-on; if not address the problem while it is out of the car. The chain install and tests could be done before pulling the engine. If it needs cylinder head work, which it may not, consider putting older heads to gain compression and towing power.
If the transmission front pump leaks at all replace the front pump seal.
New motor mounts unless they are excellent.
Paint if that matters to you.
I've noticed the vehicle is used to tow. If you are not satisfied with the towing performance, the torque converter could be replaced for a higher stall speed. Seek recommendations from others about what stall speed, I don't know the best option for this.
Melling M22HV is what I usually use. The stock pump is fine, I just like the high volume pump for a little added insurance. And no, it will NOT "suck the pan dry".
The MIGHTASWELLS add up in a hurry. With the pan off, you MIGHTASWELL check the bearings. Of course, if you are going to pull the main and rod caps, you MIGHTASWELL just put in new ones. These?Standard, not undersize? https://www.rockauto.com/en/moreinfo...=2144&jsn=2144
Of course, at 137K, it probably wants valve seals too... Can you help here, RA has a large selection
You begin to understand how this gets to a full engine rebuild pretty quickly I don't want to do this but once .
Originally Posted by Sugar Bear
Ask the shop if they will install the chain and gears then STOP putting it back together and do either a compression test or a leakdown test. This is to avoid putting it back together and installing it to find it doesn't run properly due to low compression on certain cylinders. If it tests good, carry-on; if not address the problem while it is out of the car. The chain install and tests could be done before pulling the engine. If it needs cylinder head work, which it may not, consider putting older heads to gain compression and towing power. Are you thinking the valves or pistons may have been damaged when the chain went? From what I understand it is a non interference engine so hope to gosh not. Otherwise I had done a compression test when considering a engine overhaul and came up with these compression and oil pressure results . Let me know if it would be wise to have them do another compression test.
Left bank cylinders
1 - 146, 150 wet
3 – 148
5 – 148
7 – 150
Right bank
2 - 142, 150 wet
4 – 142, 150 wet
6 - 150
8 - 150
Oil Pressure:
Castrol GTX High Mileage 20w50
Car in Park
48 at cold crank up and choke on idle of 1400 rpm
38 at warm choke off idle of 685
42 at 2000 hot (operating temperature)
48-50 at 3000
48-50 4000
30 at hot idle of 725
If the transmission front pump leaks at all replace the front pump seal. No leaks, Tranny recently rebuilt
New motor mounts unless they are excellent. I recently replaced the tranny mount which due to the engine mounts being bad tilted the engine into the shroud so I replaced the engine mounts, so they are new.
Paint if that matters to you. It matters, I've already et them know I wish to have it painted.
I've noticed the vehicle is used to tow. If you are not satisfied with the towing performance, the torque converter could be replaced for a higher stall speed. Seek recommendations from others about what stall speed, I don't know the best option for this. After having the quadrajet rebuilt it PULLS. I was starting to look into a 3.42 or 3.73 limited slip to replace the current 3.23 limited slip rear end before this happened, that is on the FAR BACK burner now.
The bearings need to be whatever the crank says they need to be. If the journals are not worn, stock bearings should be acceptable, but if the journals are worn past factory limits, the crank needs to be turned and undersize bearings used. Depending on how far off you may be, SOMETIMES you can get away with using a standard half shell and a 0.001" oversize half shell. Stock umbrella seals are about all you can install without pulling the heads to machine the guides. I haven't seen an Olds motor yet with that many miles on it where the original valve seals weren't a bunch of fragments in the valve area. And the front seal on the trans while the engine is out is one I should have mentioned, so that was a good call.
Previous compression numbers are excellent. Whether or not it bent valves...probably not unless you were on the throttle hard and it jumped significantly. If anything bent valves and probably not. Compression test would simply be a double check.
Consider supplying the paint unless you are confident they will use the correct color.
The bearings need to be whatever the crank says they need to be. If the journals are not worn, stock bearings should be acceptable, but if the journals are worn past factory limits, the crank needs to be turned and undersize bearings used. Depending on how far off you may be, SOMETIMES you can get away with using a standard half shell and a 0.001" oversize half shell. Stock umbrella seals are about all you can install without pulling the heads to machine the guides. I haven't seen an Olds motor yet with that many miles on it where the original valve seals weren't a bunch of fragments in the valve area. And the front seal on the trans while the engine is out is one I should have mentioned, so that was a good call.
I'll just ask that they determine the wear on the bearings and seals and going from there they furnish each. Will get their recommendation on brass freeze plugs also. Thanks
Last edited by MrEarl; March 30th, 2020 at 07:12 PM.
Previous compression numbers are excellent. Whether or not it bent valves...probably not unless you were on the throttle hard and it jumped significantly. If anything bent valves and probably not. Compression test would simply be a double check.
Consider supplying the paint unless you are confident they will use the correct color.
Delivered the car to another highly recommended shop yesterday. They said they were familiar with 403’s but I pulled together a few tips from several old threads here and texted it to them. Some of you may recognize your words, and thanks!!
>>>Hey guys, not sure how many Olds/403’s y’all have done, so thought I’d throw out some tips from some of the Oldsmobile gurus. Probably nothing y’all don’t already know
Because of how the bottom of the timing chain cover is almost covered by the oil pan, it is best to remove the oil pan first, replace the timing chain and cover then reinstall the pan. This will make both removing and installing the front cover easier and probably result in a better seal near the front of the oil pan and cover.
Inserted this picture provided by Joe here
They stress not to over- tighten the four 1/4” self tapping bolts that hold the pump to the front cover<<<
And a pretty good one on the rear main seal
>>>I installed one with the engine out and the crank and rods in place, with the main caps loosened, with the crank less than a quarter inch raised, by pulling the rope seal out in pieces with a pair of very long needle nose pliers, (do not scratch the surface) lubing the channel, and simply feeding the seal into the channel, facing the lip of the gasket toward the front of the motor, by firmly rotating it into position,, without trimming or modifying it in any way.
Once the seal seemed to be in position, I pressed on both edges to be sure it was seated, cleaned the end faces well, then pushed it a few degrees to get one end to poke up 3/8" so that the ends of the seal halves meet in the block and cap rather than at the mating surface, applied a small dab of silicone sealant on the ends of the seal halves to seal the ends together, and reassembled. <<<<
They were well received and they agreed to send progress pictures
and received a report that the crank looks very good, nothing bad found in oil pan bottom other than timing gear pieces, the rear main seal went in with no problems and they will be buttoning it back up tomorrow.
By the way, while looking back through the repair receipts I found where both heads and the distributor were replaced about 10,000 miles ago so not really concerned with valve seals.
Any tips to forward them on re timing the engine once it's back together?
Any tips to forward them on re timing the engine once it's back together?
Earl, it looks like the cam to crank timing is spot on. To time the distributor all they have to do is move the #1 cylinder to TDC, stab the distributor and assemble everything. Let us know what's up!
March 27th, 2020, 07:50 AM
knowing dang well I should be changing out the timing chain but with knowing the difficulty factor involved elected to take my chances awhile longer. A decision I am SOOOO regretting now. But on the positive side, the three row aluminum radiator, FlowCooler water pump and FlowCooler 180 thermostat brought the operating temperature down from 205-210 to 170-175. I'm sure that will increase when towing in the summer months but should help tremendously. While in there, I also mounted two transmission coolers onto the radiator cross member, about 6 inches in front of the radiator.
