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Chilly
04-05-2007, 12:25 PM
New here. 304 CJ5 smokes pretty bad. Heads might be loading up with oil and pumping oil down valve guides. Maybe guides are shot. Maybe Maybe I'll find the drain holes all sludged up or something simple. Or maybe the cyl and rings are just plain worn out. Haven't gotten that far yet.

To the point, what should I do to improve oiling reliability, if anything at all? I won't be revving it up like a mudder or dune buggy, and I'm certainly not interested in drag racing a Jeep. Is the stock oiling system sufficient for an engine built to live in the low and mid-range revs? Should I bother with changing to those small-hole rockers and/or pushrods? Obviously won't be drilling out any drain holes unless it gets rebuilt. Gage shows 30 psi at idle. Don't know what it shows at 4k or so.

No need to suggest reading through the forum. I've done plenty of that. Lot's of posts saying "hey, look at the photo of this rectangle with a square X. It'll answer all of your questions." Too bad the photos don't work. Seems like a lot of valuable knowledge is lost somehow.

Thanks,
Chilly

tufcj
04-05-2007, 12:52 PM
How many miles?

If it's over 80K, rings and valve guides are probably worn. The factory umbrella style valve guide seals are usually crumbled and virtually gone. There are only 2 oil drain back holes in the heads (front and back), so any sludge in the engine can clog those and overwhelm the valve seals. At 80K you're probably due for a new timing chain/gears anyway.

Start by pulling a valve cover and looking for sludge. After that, try a leakdown test, which will give you the condition of the rings/valves. If that passes, a valve job with new seals will probably cure most of it.

If it's full of sludge, a rebuild is in order anyway.

30 PSI at idle is good. There are a lot out there with less. Hopefully it's a mechanical gauge, the factory electric gauges are notoriously inaccurate. As long as you're at 30 PSI idle, and 50-60 running around 2500 RPM, you're OK. Just rebuild to stop the oil burning and run it. Most of the things like the small hole cam bearings, small hole pushrods and such are for higher RPM performance applications. If you're putting a lot of $$$$ into a rebuild, then do it, otherwise, run what you have.

Welcome to the board, and the Jeep world.

Just
Empty
Every
Pocket


Bob
tufcj

Chilly
04-05-2007, 01:04 PM
Thanks for the quick come-back. Got new valve seals but haven't had time to do the job. Also don't have a compressor handy so I'll have to get one. Don't want to pull the heads yet so I'll do it the easy way with air. If I can get it to run without looking like a destroyer escort laying smokescreen I'll just run what I got for a while, provided the oil pressure is OK. Kind of thinking it's an electrical gage so I'll get a mechanical and check it out. I just got this thing and would like to enjoy it for a while before I start rebuilding engines and doing frame-off refurb.

Chilly

Mileage reads 5100. I'm not optimistic enough to think that doesn't mean 105,100. but I could be mistaken. It's in good shape and I guess one could convince themselves that the minimal decay could be from storage in a hostile environment.

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