Projects Chevy 235 Inline 6 advice

I bought a 1950 Willys pickup. I know, the Willys site is elsewhere, but hang on. Turns out the motor is a 1959 Chevy 235. The seller claimed the engine was dead, but, I got it home and was able to get it running. I thought it ran great considering it had been sitting for years and I didn't even touch the carb. Now the truck is disassembled and the engine is out on the table (see pictures). I thought I better check the compression to confirm everything is as good as I think it is. Nope. #2 cylinder is 80psi wet. All the others are 125-130. I tested it a couple times with the same result.
Question is: Do I have to rebuild this? I trying not to overspend, but, I will do what I need to for reliability. Any comments are appreciated.

 

Did it smoke? (blue smoke, from oil burning)

Did it run a bit unevenly?

How much time and money do you want to sink into it?

How reliable do you want it to be?

How long do you need it to last, before you can spend a big chunk of money on it?

Are the #2 rocker arms moving as far as all the rest when you turn the engine?

I'd be temped to take the head off, and carefully inspect the valves/springs/seats on #2. If you don't find anything amiss, then pull the #2 piston, and carefully inspect it and the rings, as well as the cylinder bore. If you find a problem, see if there's a way that you can fix it without having to take the engine all apart.

You might be able to fix it for a couple hundred bucks, and drive it another 10-20k miles before having to spend big bucks on it. That is, if you are interested in getting it on the road, for cheap. If you just want to spend lots of money and time, and possibly never drive the truck again, then take it all apart, and do everything.

 

Jim,
It did not smoke.
It did run a little unevenly, but seemed to get better as it warmed up. I thought that might be dirty carburetor.?
The #2 rocker arms move the same as the others.
"If you just want to spend lots of money and time, and possibly never drive the truck again, then take it all apart, and do everything."
That made me laugh out loud.
I'd like to drive and enjoy it for a couple years then I'll probably sell it as I have others in the past. I have not pulled the head off yet as I know that will lead to more $$$. BTW, I've never had to rebuild an engine. So this will be new for me.

 

Leak down test #2 to see if valves are seating/sealing.

 

Just out of curiosity, does it have the 848 head on it?

 

I don't have a leak down tester . Would this do for an amateur? Or is there another way?

https://www.amazon.com/LEIMO-Cylind...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

Yes. It does have an 848 head. #3836848. Why?

 

When I had nothing a rubber tipped air hose nozzle got the job done. You just need to see if air get's past the valves with out getting all scientific with numbers because your compression tester has told you something is up. Now it's where is the air escaping that is giving you the lower reading on #2.

 

That is the best head for 235's that I am aware of. It has the best compression for all of the 235 heads that will fit that block.

 

That´s the latest 235 head with the most compression. Generally 235s are good engines. If it was mine, I´d run it for a bit, set the valve lash ( unless it´s a car engine, then it probably has hydraulic lifters) and see if #2 improves.

 

I'd just pull the head, since you need to buy most of the gaskets for it anyways, might as well get a complete overhaul set. Then you can actually see how things look, how much ridge there is, if any cylinders are scored, etc. And you can pull out any valves that look iffy.

The thing about going all out and never driving it again...that's the most serious part of my post. I hope you understand it well

btw new rings, hone job, new gaskets, doesn't cost much and can make a big difference, if everything else is still in useable condition.

 

Actually your wet compression test tells me that the problem is most likely a valve not sealing. If the wet test jumped the compression to near the other cylinders, that would point to piston or rings.

 

Little known, less cared about fact; Toyota bought all the casting patterns from GM and built them 235 engine to metric specs, otherwise identical, for Land Cruisers up into the 70s. I read reports that they didn't even change the GM I.D engravings on the inside of molds.

 

I’m with @jaracer , compression test should be done dry first, then wet on weak cylinders to compare

 

Dry test was 75psi.
Wet test raised it to 80psi
My "wet" test was just a squirt of wd40.

 

that's within the margin of error, and only tells us that oil didn't fix anything.

When will you pull the head and post some more pictures? We're all on the edges of our seats

 

Alright. I'll commit to the $$ & time. I should have the head off by tomorrow. Seems like a shame when the other 5 are so good.
BTW I thought the "most serious part of your post" referred to the type of projects that get disassembled and never driven again because they never get RE-assembled.

 

Well, Jim did say run it as is, and see what happens. But, if you want to fix it or at least find out what’s up, things have to come apart.

Hint. Use you’re cherry picker to lift the head off.

 

I had similar on my 235. Turned out to be bad valve guides in #6.
Just pull the head and look around. By the way, under load does it occasionally back fire a little?

 

that's what I meant. I just am try to nudge you back towards finding and fixing what is broke, and not fixing everything because you can.

 

Simple valve job. Maybe one valve if it is too far gone. Used to do a 216 in one day at work. Complete overhaul, that is.

Ben

 

I had the truck disassembled before I got the engine running. It had to be drug up onto the trailer when I bought it. Brakes were all locked up.

Thanks. Here are a couple of pics.
Also, I turned the table around when I set the engine on the table. It's NUMBER 5 that had the low compression not 2.
I noticed cylinder 5 was dull finish on the upper 2 ". The other cylinder were quite shiny. Almost mirrors.
What do you think?

 

OK
The head is off and in the truck.
$450 estimate to rebuild at one shop.
The other shop is $500.
I was hoping it would be 200-300.

 

$450 to rebuild the head?? I had a crack fixed and a valve job with hardened seats put in for $250.

 

Dont jump the gun. I would at least search around a bit for a non cracked head if your not in a rush. 450 is a bit much. Itll probly be more after you commit. That dont include a gasget set, fliuds, etc, bla, bla. If ya look hard enough id bet you could find a complete motor for half that. At least on da right coast....

 

Don't jump the gun!

My wild guess is the rings on #5 piston are stuck, or something. I'd pull it out and look at it before getting any head work done.

 

you might also want to pull the valves out of #5, just to make sure the exhaust valve it seating all the way around. Don't expect the seats to look nice, but they should be relatively consistent.

 

Squirrel. Look closer at the head. Its cracked.

 

I can't see it. Maybe you could provide a bit more detail about where the head is cracked?

perhaps copy the image, put a circle around the crack, post the modified image?

 

I dont know how todo all that. Look at head hanging, count 5 cylinders up. Between valves.