What I've been up to for the last 7 months. (LONG, LOTS OF PICS)

[BrianG]

So, what started off as a simple timing chain replacement turned into a complete teardown and mini-rebuild. Sometime in April of this year at ~166k miles, my timing chain snapped. To replace it, I decided to pull the engine out. Well, its a good thing I did take it out and tear it down because I came to find that nearly every valve smacked the pistons when the chain went. Apparently, the LH0 is an INTERFERENCE MOTOR, contrary to what I previously believed. I ended up tearing the entire block down to nothing but the cam and crank, cleaned it, honed it, replaced the heads, redid a lot of the wireloom, and replaced nearly every gasket. I was especially impressed to see how well the engine has worn over 16 years and 165,000+ miles. The cylinders still had a cross-hatch pattern to them, the pistons still had their casting lines in them, and most of the rod bearings looked really good. The wristpins had no play in them, and the pistons still sat tight in the cylinders. I had to ridge ream a small ridge out of the top of each cylinder which was a kind of scary operation, but really cool to see how it worked at the same time.

 

Then a little bit of trouble started. I ended up putting up the oil pan BEFORE the timing cover, which made the oil pan gasket fold under the timing cover. I didn't realize I had messed it up until I saw that I had an oil leak coming from the front of the motor. The oil leak was also worse than I had thought it was, and one morning 2 weeks after finally getting it running again, the motor was making a ticking noise and was nearly dry of oil. Putting in oil didn't help either. [:'(] I concluded rod knock. So, on a nice tuesday morning, I pulled the motor out for a second time, pulled the oil pan and inspected each of the rod bearings to find no spun bearings and NO CAUSE FOR ROD KNOCK. So, the next day, I put the motor back in. It was getting really easy to do this now. Another theory for the noise led me to check for a collapsed lifter. So, this past week, I tore apart the top of the engine in the car and pulled apart a bunch of the lifters. I couldn't find any valve lash or reason for ticking, so I put the motor back together.

 

It's driving now, but still making a ticking noise after it warms up. The new theory is that its an exhaust leak, so I'll have to check that out. Other than that, my first gear is nearly useless from a stop, but I can just throw it into 2nd if I need to get going quicker. The car is in sad shape, but its running and I'm happy with that. I'll just have to drive it into the ground and then finally do a swap.

 

Now, here's some pics.

This picture is of the front motor mount. This used to be a 'hydraulic' mount, meaning nothing but a rubber boot filled with grease. Some time ago, this mount must have failed because it left a disgusting dirty mess of grease all over the cradle which you can see a couple pics down.

In these next few pics, you can see how the valves are NOT CLOSED with nothing pressing them open. They were bent pretty bad. The darker smudges on the valve faces are where they impacted the pistons.

In these pictures of the pistons, you can see some shiny areas on the rim of the piston where the valves impacted.

This next picture is of the crosshatch pattern still in the cylinder. You can also see the shiny area around the top of the cylinder where I reamed the ridge off. The reamer just cuts off the top layer of thicker metal in the cylinder so you can push the pistons out of the top.

These pictures of the pistons show just a little wear on the thrust side of the pistons. What you cant see is that the rest of each of the pistons still have the lines from the casting still visible.

This next picture is of the timing damper. This pic also shows the old, snapped chain. At some point, the damper just got shredded. I found all the broken metal from it in the oil pan. You can see the right side of the damper just got torn apart and folded over. Compare these pictures to the new damper a few pics down to see how it is supposed to look.

 

CLEAN PISTONS!!!![&:]

The shiny spots on the top of the pistons now are where I had to grind down the sharp edges chewed up by the valve impact.

So pretty.

Rebuilt heads installed.

This picture shows really well how badly bent the valves were.

Cleaned engine bay and cradle.

Painted cradle.

Some of the guys that helped me that night. That day, I worked on my car from noon straight through to 5am the next day, got up at 9am to finish it for a w-body meet that unfortunately, the car didn't make it to.

[slick]

Thats a lot of work, especially for a 3.1. For how much money you spent on it, I, personally, woulda sourced out a 3400, and went ahead with that swap.

 

But, props for doing the work yourself, and getting it running again

[Robby1870]

That's probably the longest post in the history of posting. LOL

 

Nice work. I'm kinda surprised the chain broke at only 160k+ miles.

[BrianG]

Thanks, but there really wasnt much money into all of it. Doing any kind of motor swap would have cost way more. I got the gasket set for $100, the pair of heads for $220, and then replaced the oil pressure sending unit, engine temperature sensor, and a few wires and plugs, and then fluids, so the whole thing cost well under $1000 for everything, including having to purchase a cherry picker ($150).

 

I'm thinking the timing chain broke because of the stress of a couple months worth of driving with misfires causing the motor to run jerky. Other than that, I see no reason why the chain would snap the way it did for any reason.

[slick]

I've seen 3400's with less than 50k miles go for $400. All the parts needed woulda been less than another $300. But, i know the feeling on swapping, gotta find everything to do it.

 

 

[19Cutlass94]

Thats a shitload of work to do for a 3.1, but still least you go it running!

 

I think just fixing it like he was would be easier than a swap. Since you basicalll just have to do engine work, which really isnt bad at all, compared to swaping an engine like a 3400....

[BrianG]

Thats a shitload of work to do for a 3.1, but still least you go it running!

 

I think just fixing it like he was would be easier than a swap. Since you basicalll just have to do engine work, which really isnt bad at all, compared to swaping an engine like a 3400....

Exactly. I've never done this stuff before, but I didnt want to have to worry about coming up with custom things and learning a new engine just to get my car on the road again. Also, I live by "go big or go home" so I didn't even consider the 3400. L67 or bust, and I just didnt have the funds for it when it came time to fix it.

 

It was a great motor to work on, and I learned a whole lot, so I have absolutely no regrets about putting in the time or effort on it. It really was a blast.

[kuntzie]

nice work.

[SigEpCutlass]

Wow, I was wondering what took you so long to get it running.

 

Glad you finally got that finished up!

[GnatGoSplat]

That's a ton of work, good job!

 

Yeah, I think most engines with a timing CHAIN are interference. The thought is something else will fail LONG before the chain goes so nobody ever worries whether it's interference or not.

 

[Brian P]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

[FordBoy]

Are those heads aluminum? There is a power booster mabye 30-75hp. But all around nice work!

"Wow nice car would smoke the piss out of me!" LOL

[5speedz34]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

Are those heads aluminum? There is a power booster mabye 30-75hp. But all around nice work!

"Wow nice car would smoke the piss out of me!" LOL

 

 

Umm all 2.8/3.1 after like 85 when the went to MPFI are aluminum heads.

 

 

 

I give you props for the work!

[Brian P]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

 

Rebuilding a 3.1 complete like that. It's prob more of a reason why I want a project car for things like this, and not messing with a daily driver. I still have my 3.2L I can drop in something but I have no car for it. Seeing this thread just reminded me of all that, thats all

[5speedz34]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

 

Rebuilding a 3.1 complete like that. It's prob more of a reason why I want a project car for things like this, and not messing with a daily driver. I still have my 3.2L I can drop in something but I have no car for it. Seeing this thread just reminded me of all that, thats all

 

Yeah, I know what you mean. I feel the same way.

 

Was it bored to a 3.2L? If so how far over?

[FordBoy]

I didnt know that all of them were aluminum. Dont i feel dumb!?!?!

[intern8tion9l]

wow, i think "lots of pics" is a bit of an understatement. but great work, and one of the best things about doing something like this is learning, like you said

[Brian P]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

 

Rebuilding a 3.1 complete like that. It's prob more of a reason why I want a project car for things like this, and not messing with a daily driver. I still have my 3.2L I can drop in something but I have no car for it. Seeing this thread just reminded me of all that, thats all

 

Yeah, I know what you mean. I feel the same way.

 

Was it bored to a 3.2L? If so how far over?

 

.030 over-bored, yeah

[5speedz34]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

 

Rebuilding a 3.1 complete like that. It's prob more of a reason why I want a project car for things like this, and not messing with a daily driver. I still have my 3.2L I can drop in something but I have no car for it. Seeing this thread just reminded me of all that, thats all

 

Yeah, I know what you mean. I feel the same way.

 

Was it bored to a 3.2L? If so how far over?

 

.030 over-bored, yeah

 

I know off topic but my 3.4 is .030 over bored so does that make it a 3.5?

[Euro]

nice pics man. and i think i see me from my knees down!!!! lol that was definitly fun at least just helping you out bro!

[Mach 5]

Engine looks good. Awesome job! I don't believe that just because something needs work the whole thing should be replaced. Just fix it and maybe you'll learn something in the process.

 

Question- What do they mean by overbored?

[Brian P]

wow, familiar sights. I dunno if I'd do it all again or not. I think I'm getting too "old" for this

 

What do you mean?

 

 

 

Rebuilding a 3.1 complete like that. It's prob more of a reason why I want a project car for things like this, and not messing with a daily driver. I still have my 3.2L I can drop in something but I have no car for it. Seeing this thread just reminded me of all that, thats all

 

Yeah, I know what you mean. I feel the same way.

 

Was it bored to a 3.2L? If so how far over?

 

.030 over-bored, yeah

 

I know off topic but my 3.4 is .030 over bored so does that make it a 3.5?

 

Well a stock 3.1L is really 3.15L (191 ci) .030 over will make the displacement 194 ci = 3.19, so I rounded up 0.01L. Stock 3.4 DOHC = 205? ci which is 3.34L. .030 over would make it 208 ci, or 3.41. So you've just got a true 3.4 not a 3.34

[97loudcut]

Wow, good info Brian thanks.

[Robby1870]

Yeah, I actually just did that 3400 bored over calculation. Kinda funny when you think about it.

[Mach 5]

Thanks. How do you overbore an engine?