elpresidente

I bought a '70 350 for $200 off CL that allegedly was pulled from a running Delta some years back. It has been sitting for 3 or 4 years, has oil in it and turns free. I have been searching around and have a general idea of what I'd like to do. I'm on a scant budget so I'm planning on stripping the top down, cleaning and replacing gaskets, etc. I also want to change the timing chain. I'm new to this so if anyone is willing to share any tips or pointers, I'd be extremely grateful. I'm hoping to get it done and dropped into my '77 Cutlass Supreme in time for the Olds Homecoming.

TIA.

Fun71

If the heads have never been off then I would not take them off until I absolutely had to. The factory head gaskets were thin stamped steel and the aftermarket replacement gaskets are thick composition. Simply changing the head gaskets will drop the compression ratio due to the difference in gasket thickness.

elpresidente

I had no idea. Great tip! Thanks for that!

MDchanic

High or low compression? Any idea how many miles?

It is definitely a good idea to check all the bearings, and probably replace the shells, unless they're really nice.

If it's a high compression motor, and you don't want to use an octane booster to get your fuel up around 95 octane, using the standard Fel-Pro head gaskets to reduce your CR to around 9.6:1 may be beneficial. If it's a low compression motor, I wouldn't advise it.
You can get the original 0.017" shim head gaskets from Smitty (M&J Performance) if you do decide to pull the heads (it's always nice to have a good look and clean up the combustion chambers), or you can have the heads milled about 0.025" to maintain compression and valve train geometry, and use the Fel-Pro types.

- Eric

oldsman72

Welcome to the site, elpresidente!
In 1970, there were 2 versions of the 350, a high and low compression motor. I had a 2bbl version, which was low compression. I believe factory 4bbl motors were high compression (but I'm sure I'll be corrected if that's not the case).
Good luck with your build!

elpresidente

It is the 2bbl version. I'm planning on taking the 4bbl intake and Q-Jet off the 307 I'm replacing for use with the 350. My understanding is that this shouldn't be an issue.

elpresidente

Also, I had a question on the numbers. The casting code is 395558 2 and the number under the head is 31M171713. My research has indicated that this means it was in a '71 car built in '70. Am I right? Also, #7 heads.

Fun71

Well that VIN and #7 heads means it's a 1971 engine.
1970 350s used 6 heads
1971 350s used 7 heads
1972 350s used 7 A heads

The '71 and '72 350s were all advertised at 8.5:1 compression ratio (both 2bbl and 4bbl) but in reality were closer to 8:1, which makes the head gasket choice even more important so you don't end up with 7.x:1 compression ratio.

All of the above heads have the same combustion chamber sizes and the compression ratio was changed by using a different size dish in the piston. The '71 and '72 pistons have huge 24cc dishes compared to 6cc for the high compression 4bbl 70 engine and 14cc(?) for the low compression 2bbl 70 engine.

elpresidente

Good info. Thanks for that!
I do have to admit that I'm getting a bit confused. I looked up the number on the exhaust manifold - 380001 LH and this site says they were used from '63-'70. Regardless, I'm excited about what I have.

Fun71

Yeah, well that info also says it was used on the 350 engine from '63-'70, yet the 350 didn't come out until 1968, and the 330 came out in '64 so exactly what engine was that manifold supposed to fit in '63?

elpresidente

Right. I'm guessing that the exhaust manifold was "left over" parts that got used up. Being new to this, it was just a bit confusing to me. I think I get it now.

I'm hoping to take compression readings tonight. I'll post numbers when I have them.

elpresidente

So it looks like I'm getting 0 psi on several cylinders. Battery started to die with the 5th cylinder I tried.

1 - 155
3 - 0
5 - 0
7 - 127 (battery started dying)

2 - n/a
4 - n/a
6 - n/a
8 - 78 (battery pretty much dead)

So what might I be looking at? Valves? Timing chain? Hole in the piston? I'm getting anxious to start taking it apart. I don't have a leakdown tester but could have one in a day or so. Should I absolutely do a leakdown test before disassembly?

MDchanic

Low compression on two adjacent cylinders brings to mind a failed head gasket, but ZERO compression seems unusual.
Catastrophic failure is not excluded at this point.

I'd charge the battery, give it another shot (all spark plugs out, throttle wide open, or carburetor off the engine, or intake off the engine for that matter), and if the result is the same:

OFF WITH THEIR HEADS!!

- Eric

Seff

You're waiting for the compression stroke, and not just the exhaust stroke, right?

ELY442

If you are going to replace the gaskets, here's a good time to replace that rope seal in the rear main cap and switch it over to the neoprene seals. You be glad that you did this now than later.

elpresidente

Bad news.

nsnarsk65cutlass

Ugh,not looking good sorry to see that.Nick

elpresidente

It may not be clear in the picture but that dark spot in the middle of the valley is a half dollar sized hole.

MDchanic

Yeah, it's completely not clear.

May as well spend the half hour to tear the rest down and take a few more pictures, so you and we can see what happened.

Guess that Delta didn't run too well when the engine was pulled out of it.
Why even save an engine like that for years?

You may still end up with a stack of good parts.

- Eric

elpresidente

Yeah, I'll tear it down today. It will take me more than 30 minutes, though. The guy I bought it from picked it and a '79 350 as "spares" a few years back. I don't think he had any idea. Maybe I'm just sucker.

Not sure where this puts me. I'll probably have to cut my losses for now and repair the head gasket on the 307 I have. Would #7 heads be worth the trouble of putting on a 307 (are there any issues?). I think perhaps I should go that route and find a good 350 block and build from the ground up. I am curious as to what parts could possibly be salvaged from this 350.

Thanks for the feedback. More pics to come. Regardless of the disappointment I feel right now, I have been having a great time working on this and learning as I go.

Octania

Might just be a slipped timing chain.
That "hole" in the valley might be just a hole thru the GUNK, not thru metal.

At this point, I know you said $ is tight, but you simply must tear it down 100% and see what you have and don't have. This road can be very long and expensive depending on how bad it is, what your standards are, and what local machine shops charge.

Could be anywhere from a simple refreshment with a hone job, new rings and bearings and a cheap cam, and head job.... to nothing useful exc. head cores.

Where are you at? Head jobs vary in price, and the price they advertise is typically for a Chevy head that needs NO PARTS. When you get YOUR heads in, they "need" valves, guides, seats.... and the bill comes in at $800 easily. By now you mightaswelled your way into the $1100 brand new AL heads. SOME technicians will rebuild with used valves if the guides are not too bad, especially if you sign off on not making trouble if the engine ends up less than perfect. I have found a guy that does good head work for reasonable cost, and does not sell me stuff they do not neeeeed.

If the bores are usable, you can remove the gunk from the pistons' ring grooves and oil return holes, and re-use them. That will save several hundred in pistons, boring, piston exchanging, etc.

New bearings is a given, as well as a timing set.

Sometimes you get lucky, even in a gunked engine, and the crank journals are fine. Other times you find a pounded bearing and it needs the crank kit. Last time I did a 403, it had a bad crank, the entire ground crank with bearings was only $200... but instead I went the more expensive route of fitting a forged 330 crank in there.

Many of us here have cheap parts that can help. Camshaft, etc. I have a 350 engine kit with pistons somewhere. Not too pricey. I have a barely used all-steel timing set I would donate for the price of shipping. Cams are around, but you may have to settle for what's handy instead of what's perfect for your compression/ gearing/ etc.

What 307 4-bbl intake are you trying to use?
Looks for the intake ID in the depression behind the thermostat- either A4 or A5 in huge characters.

You will want to start a spreadsheet and list what you may need, and what it costs, with a sum total shown.

Valve sets can be found on epay for reasonable prices.
Rockauto.com will be your friend too.
Look into National Automotive lines- Natauto.com I believe.
And your local machine shops.

MDchanic

Really? Balancer, intake and water pump are already off, timing cover, gears and chain should be fast, 20 head bolts and the heads are off, oil pan bolts are no problem, and with 28 bolts and crank, oil pump, and pistons are out.
With air tools, it goes fast.


307 heads should have roughly the same volume as earlier SBO heads. Why do you want to change them?

- Eric

elpresidente

If it isn't clear by now, I am new to working on cars. That's one reason I really appreciate all the advice people here offer. Having said that, I don't have air tools. I have a basic set of tools to work with. Often, I try something, it doesn't work, then I do some research, that doesn't work, etc., so I'm a slow mechanic. I don't mind. I enjoy the work. I do consciously take my time, both for enjoyment and so that I learn as much as possible while doing it.

Thanks for the tip re: heads. I wasn't sure.

MDchanic

Ohhhhhh... Couple of hours, then.

You should get a half-inch drive air wrench, though - terribly useful.
Get a good one. It makes a big difference.



My grandfather used to say, "I'm not a slow mechanic, I'm not a fast mechanic - I'm a half-fast mechanic."

- Eric

elpresidente

I'd have to get an air compressor first, right? It will take time but I will acquire the right tools eventually.

MDchanic

Oh. I thought every house came with one.

Watch the yard sales.

- Eric

elpresidente

So what have I learned so far?

1. Make sure it turns over before buying. It did turn but I didn't know until I got it home.
2. Take a battery, starter and compression tester to test before buying? Unless I can see it run, I should require this before any engine purchase in the future. Is this too much to put on a seller?
3. Expect the worse.

Off to the garage I go. The balancer nut has been stubborn thus far. I have to find a way to crack that (without a breaker bar - lol). More pics to follow.

Thanks for the advice all. Hopefully I can eventually give to this community at least what I am able to take from it now.

elpresidente

It should be a law. I recently moved to the country. 98 acre farm that's been in the family close to 100 years. My Grandpa's old compressor is out in the grainery. I might drag that out later and see what trouble I can get into with it. With luck (HA!), I can get it running enough to run air tools. Then I'd HAVE to buy an air wrench, right?

Octania

Another option is a NAME BRAND cordless [or corded] impact.

There is little that a Snap-On 18V or better impact won't remove.

For the balancer bolt, an impact will do wonders.
An alternative, if the engine will hold still, is use vice grips on the flexplate, butted up against the block, to prevent crank from turning. Then use a breaker arm- actually, just get one of these:

http://cgi.ebay.com/ebaymotors/Craft...item43c86c1a4a

Acts as a speeder after the main bolts are loose, etc.
You will need a TWELVE point 9/16 socket with thin walls [not Chinesium] for the rod bolts.

elpresidente

Thanks for the tip. I have vice grips on the flexplate and am using a 1/2 drive ratchet with a long pipe on it. It's been soaking in PB Blaster all night. I'll give it a shot soon.

I actually have a 12 point 9/16 socket I believe. From a craftsman set my brother bought for me when I bought this Cutlass. The 1/2" drive sockets are all 6 point except for the 9/16. Must be fate, right?

ELY442

Sears always have a Craftsman promotion every weekend. You can get the socket set in a affordable price.

MDchanic

See? Every house DOES have one.

Use the longest lever you can find or make on that balancer bolt - it was put on with about 200 fl/lbs about 50 years ago. PB Blaster won't help with that one.

If a single pair of Vise-Grips on the flexplate won't quite work, try two or three each one backed up against the one in front of it. Increased gripping surface area will help.

- Eric

ELY442

If the vise grips doesnt work, i use a chain on one end to bolt to the rear crank and the other end of the chain bolt to the rear trans housing (engine side).

elpresidente

I'm such a moron. The hole I was worried about is supposed to be there. With all the gunk on there it did not look that way. After cleaning it off, it's clear now. Obviously, I have a lot to learn.

Now to figure out the best way to clean this crap up.

MDchanic

So, since you posted your first and only picture, which you admitted was unclear, and which I couldn't make heads nor tails of, have you taken any others that might actually help us to help you to figure out what's going on?

- Eric

elpresidente

Thanks for all this info. I have started a spreadsheet. Good advice. My main priority is to get this engine up and running as cheaply and quickly (for me) as possible.

- I live in Michigan, in the Jackson area. I got a quote to have the heads milled for $30 each but it sounds like I'll need more work done. My concern is that I don't have the knowledge to tell someone exactly what I want done. Research and patience should overcome that challenge, I think.
- I plan on cleaning the gunk out and taking the heads off tonight, along with the oil pan. I'll post pictures here. Will that be enough to see everything I'll need to know?
- I will plan on purchasing bearings and a timing set, neither of which look overly expensive. I would gladly accept the timing set you offered. I can PM you and make arrangements that way, if you prefer.
- An engine kit is probably outside my budget at this time, even one that's not too pricey. I'm hoping to reuse whatever I can but If that's not possible, it might just take longer to complete the job.
- As for the camshaft, is that something I should plan on replacing? Or will that be determined upon inspection?
- The intake off the 307 is a 17. I understand that it is identical to the A4 but cast iron with less casting flaws. Not a good intake but I need the 4bbl and an after market intake is an expense I can't take on.

Thanks for the help.

Octania

Thanks for all this info. I have started a spreadsheet. Good advice. My main priority is to get this engine up and running as cheaply and quickly (for me) as possible.
===============
I can help with that.


- I live in Michigan, in the Jackson area.
===========
perfect. I can direct you to the guy that can do your heads affordably. He's in Lansing, as am I.


I got a quote to have the heads milled for $30 each but it sounds like I'll need more work done. My concern is that I don't have the knowledge to tell someone exactly what I want done. Research and patience should overcome that challenge, I think.
==============
The head man will fix it right and affordably.


- I plan on cleaning the gunk out and taking the heads off tonight, along with the oil pan. I'll post pictures here. Will that be enough to see everything I'll need to know?
==============
Probably. Gasket scraper and screwdriver onto newspaper or simialar for the big chunks, then fresh newspaper and some brake or carb cleaner and a brush will get pretty good results. Generally one just takes it to the machine shop and they blast it clean, but on a zero budget, you CAN make do with a good hand cleaning. You will want to remove the freeze plugs and the oil passage plugs and DO NOT LOSE the left rear plug with a square recess and the spurt hole.


- I will plan on purchasing bearings and a timing set, neither of which look overly expensive. I would gladly accept the timing set you offered. I can PM you and make arrangements that way, if you prefer.
================
I have numerous lightly used timing sets from rebuilt and then scrapped engines. Serviceable for many years, and FREE.


- An engine kit is probably outside my budget at this time, even one that's not too pricey. I'm hoping to reuse whatever I can but If that's not possible, it might just take longer to complete the job.
==================
I have ring groove cleaner, ring expander, other tools that may help. If I can find them.


- As for the camshaft, is that something I should plan on replacing? Or will that be determined upon inspection?
=============
pretty much a might as well thing. At LEAST put a Toro cam in there. You can/ should only re-use the cam it had if you put all the lifters and pushrods and such in order in a holder so they can go back in the same hole. A new set of lifters is dirt cheap and good insurance. Your rockers are probably work- the pivots especially. I have good used ones if the small price for new is too much. At least you don't have to re-use really worn parts.


- The intake off the 307 is a 17. I understand that it is identical to the A4 but cast iron with less casting flaws. Not a good intake but I need the 4bbl and an after market intake is an expense I can't take on. Thanks for the help.
=================
The #16/17 egr intakes are OK for what they are. Why not just use an A4? There are two at the local boneyard right now, I think they charge like $30 or so for one.

http://www.u-pullandsave.com/Price_List.cfm#4

You need to schedule a visit to Lansing.

elpresidente

Wow. Thanks for that, Octania!

I work in Okemos so I am up here every day. I have to be on site from 7-9am and 3-6pm but other than that I am available. A meetup would be great. Whatever is convient for you.

And I will likely be pulling an A4 from somewhere. That is a good idea and worth it, imo. Plus I get to do another first, acquiring a part from a junkyard.

elpresidente

Well, here is what I'm looking at. I'm going to need the spring tool to get those off so that may wait a day or two. Tomorrow night, I plan on removing the balancer an then the crank. I'm also going to pull the timing chain off.

MDchanic

Wow. Gunky.

But no holed pistons, bent pushrods, or stuck valves to explain the two cylinders with no compression.

Were there signs of head gasket leakage?

- Eric