Running terribly

[Sle-z_90]

3 cylinders with no compression?

Time for a leakdown test. If you've got leakage past the valve(s), you'd need to verify lifter preload, and if that's good...the engine needs the heads removed for valve work AT MINIMUM.

If the leakage is past the rings--or holes in the pistons--the engine is pretty-much "done" and needs a proper rebuild.

And if the leakage is from one cylinder to another, you can HOPE that a new head gasket will fix it.

thank you. This is great info. Hopefully, the leak down test will be conclusive.

 

[Sle-z_90]

Well, to put a bow on this, I ran a leak down test on two cylinders, both were leaking into the intake. I pulled the intake and passenger side head so far and the cylinders on the side at least have are glazed and have a fairly substantial ring ridge. I think my options are full blown rebuild or some sort of engine swap. Thanks for all the advice. I think this has been a good experience.

 

[Erik the Awful]

the cylinders on the side at least have are glazed and have a fairly substantial ring ridge.

Ring ridge or carbon ridge? These motors don't usually get any ring ridge. If you have blowby, it's because the rings are worn.

 

[Sle-z_90]

Ring ridge or carbon ridge? These motors don't usually get any ring ridge. If you have blowby, it's because the rings are worn.

How would I tell the difference? Tbh, I’ve never heard of a carbon ridge so I just assumed. Below are a couple pictures and a video link.

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[Erik the Awful]

Carbon ridge is just a buildup of carbon on the cylinder walls above where the rings wipe. It can be scraped off. True ring ridge is where the rings have worn away the cylinder bores, leaving a lip of metal. Typically ring ridge requires a ridge reamer to remove the pistons, and then the block needs bored. With a carbon ridge there's no real bore taper and you can just hone and reassemble.

 

[Schurkey]

Does it dissolve in solvent (Carb spray, for example.)

 

[Sle-z_90]

It didn’t come off with carb spray and elbow grease. Also, I’m only looking at passenger side but the ridge is more prominent on cylinders 2 and 8. It clicks with my fingernail as shown in the video. However in cylinders 4 and 6 I wouldn’t say it “catches” my fingernail.

 

[Schurkey]

A cylinder bore gauge would confirm, but you're likely looking at a re-bore + torque plate hone, and oversize pistons.

 

[Sle-z_90]

A cylinder bore gauge would confirm, but you're likely looking at a re-bore + torque plate hone, and oversize pistons.

There may be bigger issues around the corner when I disassemble. Ideally, I'd like to just do a backyard rebuild to get it running while I save up to LS or BBC swap or build it into a 383. However, would using a ridge reamer and stone hone tool be a terrible idea in this situation? I'm not needing it to make 400hp or last another 100k at this point in time. If I could get an honest 300hp and have it last 2-3 years, that would be awesome. So, if I could ream the ridge, get one of the performance rebuild kits from Enginetech, and some vortec heads and intake run it 2-3 years that would be awesome.

 

[PlayingWithTBI]

So, if I could ream the ridge, get one of the performance rebuild kits from Enginetech, and some vortec heads and intake run it 2-3 years that would be awesome.

Does your block have the bosses for a roller cam? If so, get one, it'll last longer and give you better performance vs the same duration as a Flat Tappet one.