Projects Rebuild or replace ?

My 364 Nailhead has got pretty low compression on one and fairly low on one more. I am in a quandary about take it out and rebuild or just drop in a 350. If I change it out, as most of y'all know, that means new drivetrain all the way back due to Buick's enclosed driveshaft. I would rather have the nailhead rebuilt but am being told they are pretty expensive to rebuild. Anybody got any thoughts for me ?
Thanks

 

There’s a few reason’s for low compression. Does the engine smoke and or use a lot of oil?

 

If the rest of the drive train is decent the swap might be more expensive than a rebuild.
Are you doing it all yourself?
Are you happy with the buick trans?

and have you figured out why it’s low?
Could be top end

 

I haven't ran it long enough to tell a whole lot. It needs some wiring work before it can be really tested. The coil was getting hot as well. What time I have been able to get it running I haven't seen smoke. It has sat in my garage under a cover now for a long time due to finances. I had a friend come over and work with it a little bit and he says I don't have enough spark to turn it over sufficiently to start it. So not having been able to start it long enough I am not even sure what the transmission's condition is. I am very limited in ability and I have not even been able to find a shop in this area that will take it in unless I go to one of the very expensive hot rod builders. The body is real good on the car and that's one reason I have held onto it. It is a rare, 3 speed 2 door post car and I had such high hopes of getting it fixed up.

 

"3 speed 2 door post car"? Don't change it.

 

Engine swap means a lot of other money.
removing the torque tube in a Buick we did meant changing not just the rear end but the entire rear suspension as well.
Wiring will have to be handled no matter what engine you use.
Finding a shop to trust is tough.
Building the Buick is still probably the best bet money and time.
The individual Buick engine may be more than a 350, but it’s already there. No mounts to build, no drive shaft to deal with, the rear end is already set up.

 

Since it is a stick, I vote for fixing the nailhead. It's got the torque to move that big Buick. I'm very happy with my nailhead.

 

Yes sir, I fully agree with you on this. I like the idea of keeping the 364. I will check around on a good shop to rebuild and see what I can find out.
Thanks for the good input you guys !

 

I’m assuming your friend did the compression test?

Did he do a wet test as well?

 

Please pardon my ignorance but I am not sure what a wet test is. What he did was he took a test light and hooked it up to some of the different spark plug wires and he determined there wasn't enough spark that he felt would be sufficient to start the engine. Previous to that my other friend had checked each cylinder with a compression tester and those readings were accurate. Even with a hot battery and gas poured down the throat it tries to turn over and it has in the past and even started but now it doesn't seem to have the energy to start.

 

Could be as simple as a bad ground at the distributor, cleaning up all grounds and battery contacts may solve the weak spark issue.

 

I think the early 401 (pre-1964) bolts up to that same bellhousing, if you were going to do an engine swap, I'd do it with a bigger Nailhead. Factory stickshift in a Buick is pretty rare by 1957, as is a 2 door sedan. I'm not sure if there are any Chevy bellhousings that would mate a 350 to a '57 Buick stick trans without some machining/reworking. There might be, but if there isn't, a 350 swap would be a lot of work.

 

Next would be cleaning the points and cap/rotor, a little shot of wd40 on the contacts works most of the time but if it’s really bad a scuff with 400 grit sand paper

 

Only a small percentage of those cars were manual, and the 364 is a good engine. What was the compression when tested? I would evaluate those readings, it may be rusted out head gaskets. It is true that Nailheads are more costly to rebuild, but in the long run considering the cost of a swap it may not be.
Those engine blocks have a high nickel content, and not prone to cracks other than right beside the starter. I have one apart right now, and a 401 in the machine shop.

 

I can't agree with you enough on this. Yes, the Nailhead is expensive to rebuild, but if the rest of the drivetrain is in good shape, you're trading one expense for another. The money is basically a wash. All that you're left with at that point is the additional time and work to reengineer a completely different drivetrain in.

 

Low compression can be from a number of possible sources. Rings are the most obvious one, but I just had no compression on one hole on my 455 Buick. It increased to about 50 with some oil in the hole. It was a carboned-up valve hanging open. It turned out all the exhaust seats were hammered out of it.

Your compression could be from valves stuck partly open due to sitting for so long, a bad head gasket, or any number of worse things. I would put my money on a more minor issue and if you can get it running, you'll be able to diagnose it further. As I said mine was reading no compression in one hole and it still ran fairy well.

Did he pull a spark plug and make sure they're actually firing? If the car has been sitting for ages, you could have corroded connections causing a loss of voltage to the coil. What happens if you jump the coil to the battery to get a full 12V? Does it sound like it has some compression when turning over?

IF you indeed have a dead hole, you can pressurize the cylinder to find out where the air is going as well.

 

Any 364 (57 through the end of production in 61) would be a bolt in, and the bellhousing bolt pattern is the same with the later engines (364-425). 401 and 425 engines are wider, and would need a complete engine to put in. The crankshaft had a smaller pilot hole in the 64-66 engines, but with a manual presents no issue. 401 and 425 engines are also counterweighted differently, so a flywheel from them would be required, which is a rare item.

 

Instead of a full rebuild we could do a old school rebuild, rings, bearings, gaskets and check the valves with kerosene and lap them or a full valve job as needed. A lot cheaper than a “modern full rebuild”. The one draw back it may only last 40 to 50 thousand miles, or about 20 to 30 years for the average guy.

 

A couple of low readings on an engine that has sat for a long time, doesn't mean you're looking at a rebuild. As @05snopro440 mentioned, there are numerous, less severe, reasons it is low. Do some more testing, to get you in the right direction. Could just need to be run. I like adding a couple pumps of Marvel Mystery Oil in each cylinder well ahead of time. Also, have used ATF.

 

I think you need a little help.
I had a long reply. I think what your car needs now are really the little things. I think a few days of really cleaning up stuff, simple stuff will help a lot. At least you'll have a better idea of where you are at with it.
I thought I may know that car but the 57 I knew of was a Super.
I'm in Blount County and if you are fairly close, I would be honored to help you with it one day. I'm no expert by any means but I do have some experience bringing old stuff back to life. Most of the time it's simple stuff.

 

When I get home I will post up my readings from the test. My friend bypassed the accelerator starter with a push button below my dashboard. He can't help me anymore and there is one wire coming from the coil I am not sure about and he can't tell me anything about it. When I try hard to start it the coil gets hot. I replaced the ballast but that didn't seem to help.
Are you guys have been very kind to offer your responses and I am very grateful for all the information you're sharing with me.
Troy

 

Sir you have no idea how much I would be open to you coming over. I live in Madison County and my car is in my garage where we can easily work on it. I would be very glad to make it worth your time!
Troy

 

Seem’s you’ve got your self a Derek look alike.

 

I vote to rebuild the nail head. No change over problems, motor mounts, engine accessories if any etc. Besides the cool factor of the nail head is enough for me to keep it if it were my car.

.

 

F1, very nice offer, my bet he has a runner with a little help and tlc in the electric system.

 

That's a very kind offer.... good on ya!

 

You need someone like @F-ONE to help. As others have mentioned, this sounds like a simple fix - cleaning points, maybe cleaning some grounds, etc. Once you get it running again, let it run for a while before you do a compression test. That way, if you have piston rings that are sticking, that will give them some time to free up.

Also, don't focus on the PSI from your test; what you want to focus on is the variation between cylinders. 10% variation would be mighty fine. If it varies more than 10%, focus on those cylinders that have low compression. If you add oil to the cylinder and re-test and the compression comes up, it's rings. If oil doesn't change anything, it's top end.

You can also find a dead cylinder by using a laser temp gun when it's running. Point it at the exhaust manifolds right at the heads and dead cylinders will read cooler.

BTW - sounds like your buddy put a temporary wire (alligator clips on each end?) from the battery to your coil, effectively hot-wiring the ignition. If you leave that on, it will ruin your points.

 

I think he hard-wired it from the starter. He wired in a toggle switch as well as a push-button, both below the dash. Both work and when I hook up the battery cables to try and start it, I pour some gas down it and push the button. It turns over, and has started in the past but it doesn't stay running due to fuel lines not being connected plus carb probably needing rebuilt. The longer I crank it the hotter the coil gets. This is the part that is unnerving to me.
I am sure something electrical needs fixed, just not sure what
Maybe when I get home I can take a picture or two of all this and post up.

 

I would not use a 350” Chevrolet…..Nothing wrong with a 350” Buick engines. Might be a little pricey too. They started in 1967 and were used for 13 years I believe about the same run as the nail head. Some call the the baby brother of the 455” Buick.

 

Why is a nailhead so expensive to rebuild ?

There are many that throw money at an engine,,,,,,and still end up with a stock running engine .
If the block is good,,,,,it only needs cleaning,,,,,,and maybe a rebore,,,,right ?
Cam bearings,,,,core plugs,,,,right ?

If the crank is good,,,,,it needs a polish,,,,right ?
Rebalancing is completely unnecessary,,,,in my opinion .

Rods,,,,,if look good,,,,,need cleaning ,,,,resizing is unnecessary,,,,,stock rebuild .
Rod bolts are probably okay,,,,,,new ARP rod nuts work great on this .

Pistons,,,,,,cast replacement,,,,,,no need for expensive forged on this application .

Cam and lifters,,,,,,regrind stock cam,,,,,like new then .
Timing set,,,oil pump,,,rings and bearings,,,,,that’s a complete short block .

Basically no more money that any other engine,,,,,this far .

Heads,,,,,Mag , and surface to ensure they are flat,,,,,check the guides,,,,,valve job .
And whatever might be needed to complete the build,,,,,,,similar money to any other build ?

I have seen blocks align bored when it was not necessary .
Blocks bored when the bores were still in specification .
Cranks ground and or rebalanced when it was not necessary.
Rods resized when it was not needed,,,,,,those rod caps will be .001 or better oval again after about 2000 miles,,,,(it’s the bottom,,,,,the load rides on the top .)

Yes,,,it’s fine to do all that stuff if you want,,,,,,but don’t feel compelled to do it .
And besides,,,,,,it probably won’t be driven 50 thousand miles in the next 50 years anyway .

Nailheads were very good engines,,,,right ?
Pretty straightforward rebuild in my opinion,,,,but,,,,what do I know .
There are some good guys that will help you with this I’m sure ,,,,,go for it .

Tommy