Jezza's Turbo LJ
- Thread starter Jezza
- Start date
.... did we already blow the head gasket, or are we somehow porting it for better coolant flow or something?
OP
No, I was still getting small flakes of glitter in the oil filter after 3 oil changes. Nothing was knocking, so I had a hunch it may be cam bearings. I was right. I used a borescope through the OPDA hole and saw the bearings were squished out at the bottom. So, I pulled it to replace the cam bearings and put a lighter valve spring in. I also polished the cam journals and replaced the expansion plugs. It looked to me as if the machine shop installed the cam bearings incorrectly. The front two were installed at 2 o'clock with the oil feed holes lined up with the block. The rear two however were clocked at 12 and the feed holes were blocked.
wow...with as many stories as I hear about machine shops screwing up engines...I guess that is something else I'm going to need to learn to do.
Yup. That would certainly do it. That’s a pretty rookie mistake for a machine shop.
I hereby bestow upon you the coolest freeze plugs on a Jeep I6 award. Keep the speech short and don't mention Will Smith's wife please.
I think I got screwed by my last machine shop too despite taking it to a high end race shop. I'm just gonna run it until it blows though
OP
I bought this machine earlier this year for that exact purpose. I keep looking at auctions for more stuff. I would like to get a wash cabinet, crankshaft balancer and cylinder honing machine. I think with all that stuff I should be able to do quite a bit of engine work in house.
That’s a nice one. I have a VF5 with a 5th axis. It’s amazing what these machines can hold for the price you pay. Very good value.
I hereby bestow upon you the coolest freeze plugs on a Jeep I6 award. Keep the speech short and don't mention Will Smith's wife please.
I think I got screwed by my last machine shop too despite taking it to a high end race shop. I'm just gonna run it until it blows though
I mostly hear about assembly issues. It’s not just the I6, either. My other project, the 78 gmc motorhome, seems to have even more horror stories about shops rebuilding the big block olds like it’s a big block Chevy and really screwing them up.
I think I got screwed by my last machine shop too despite taking it to a high end race shop. I'm just gonna run it until it blows though
Damn, what symptoms are you dealing with?
Big Black Object?
Big Block Oldsmobile. And it's blue
I won't go in to all the back and forth I did with the shop just getting the work done, but suffice it to say I am almost certain they sent it out to some other shop to have the work done and didn't do most of the high end specialty stuff I paid for like using a torque plate, line boring, and spin balancing to name a few things. They sure did bead blast the block though despite me saying I didn't need it (and charged me for it)
It had a TON of sparkle in the oil and filter pleats on the first oil change after break in. It has gotten dramatically better since, but there is still a nice shimmer in the oil (nothing visible in the filter). I think it's bearing material. Hopefully they just epically screwed up the cam bearings and they clearanced themselves similar to what Jezza saw. Those bearings aren't *as* crucial to have perfect like the main & rod bearings for example.
What do you mean? Just not paying attention to olds specific assembly techniques and trouble prone areas?
The olds needs some special care in the valve train, from what I understand. I’m not exactly sure, as I’m not up on the engines as I need to be. I only know they are different than a standard Chevy.
OP
I agree this is the 9th or so Haas I've bought. They have all been decent for the price. I have a little TM1 that I prototype stuff on most of the time.
OP
It's always beneficial to find that "guy" who knows all the model specific tweaks.
OP
Big Block Oldsmobile. And it's blue
I won't go in to all the back and forth I did with the shop just getting the work done, but suffice it to say I am almost certain they sent it out to some other shop to have the work done and didn't do most of the high end specialty stuff I paid for like using a torque plate, line boring, and spin balancing to name a few things. They sure did bead blast the block though despite me saying I didn't need it (and charged me for it)
It had a TON of sparkle in the oil and filter pleats on the first oil change after break in. It has gotten dramatically better since, but there is still a nice shimmer in the oil (nothing visible in the filter). I think it's bearing material. Hopefully they just epically screwed up the cam bearings and they clearanced themselves similar to what Jezza saw. Those bearings aren't *as* crucial to have perfect like the main & rod bearings for example.
I had a hunch there was a problem after the 3rd oil change with glitter. I was able to diagnose it through the distributor hole with a borescope at a tight 90 degree to see the bottom edge of the center two cam bearings. I could clearly see they were smashed out at the bottom, then off with the pan for further inspection, and ultimately out with the engine for cleaning and repair.
OP
Also fwiw I found out the valve springs I have are 120+ on the seat with a 250 rate. The OE springs are 70 or so seat with a 200 rate. I found another comp spring that has the same dimensions with a 90 seat and 190 rate that's good for 550 lift. From reading what others have posted it seems like heavy springs cause cam bearing issues as well.
OP
Well it lives again. The valvetrain sounds a lot quieter. The valve springs are quite a bit different looking. Definitely softer on the seat. I also installed the fuel pump and moved the tank back to the TJ position to give the diff a bit more space.
