Got a Jeep Go-Devil engine with a stuck exhaust valve. Had the engine over-hauled 8 years ago. Been sitting in my garage, 'cept for a few months outdoors and may have gotten some rainwater in one cylinder. Exhaust valve on front cylinder is stuck open. I've got good compression in 3 of 4 cylinders and no compression in No. 1, so I assume the exhaust valve in no. 1 is open. Also, I can blow compressed air through cylinder one out the exhaust; further proof exhaust valve is stuck open.

Any ideas how to free up that puppy without pulling the head? I might could spray hell out of it with ATF cut 50% with acetone. They say that's a good penetrant. Any other ideas from you experienced wrenches would be appreciated.

Thanks,

Jordan

Hi Jordan

Have you tried synthetic oil. It is a very good cleaner and helps break lose stuck valves.

Change your oil with Mobil one and run it for a few hundred miles and it should free your stuck valve.

Watch out the oil is if left in an older engine too long it will start to eat the gaskets.

How quickly do you need her up, Rob ?

Any kind of penetrant that you can get down the valve guide would be good. Just not WD40.(but if that is all you have..) Just realize you may eventually dilute the oil and need to change it after you get it unstuck, and don't rev the wiss out of it. Does it have a side cover plate that you can get access to it? Remove the exhaust manifold and look with a scope, spray down the guide directly? Get it on compression stroke and push it down physically?(just be gentle if you can reach it with a bar or blade). Diesel in the oil and just let it idle?

Any of these could work. Is it really that hard to get the head off?

ETA, just found pics of it online with a side cover to access the lifters for adjustment. May want to take it off and verify problem and see what can be done to free it up. Also look like you would be able to get penetrant down the guide with the exhaust manifold removed.

Thanks Guys. She ain't runnin just yet so I can't fire 'er up and loosen 'er with oil circulating. Yes. Cali, it has side cover plate. Hoping to avoid pulling head or side cover.

Think I'll soak her with Kroil or maybe ATF cut 50% with acetone (hear that's the best) and then try Freeze-Off sprayed on the stem through the spark plug hole and see if she'll pop. They say that stuff works real good too.

Thanks all for the advise.

Jordan

Kroil is good stuff, but if you can find it, try Zep Twister. Have used all sorts of stuff on truck, tractors and motorhomes, that Twister does a hellava job.

I would try sea foam

Drain a quart of oil and replace it with a quart of transmission fluid. Run it til it gets to peak operating temp. I'd drive it kinda hard to get it over 200f.
Drain the oil and replace the filter. Replace it with a synthetic oil and a quart of Lucas Heavy Duty Oil Stabilizer.
If you run it a hundred miles after all of that,and it's still stuck,send it to an auto machine shop for a valve job.

I've loosened frozen diesel engines with ATF and diesel - I'd be afraid of the acetone. I'd think it'd be hard on bearings, etc.
I've also found that time is your friend when using solvents - be patient.

Mark

With the side cover plate off, a coupla' bumps with a bar or a polished screwdriver would probably get the valve freed up.

If I had the (today's) price of a good rebuild at stake, I'd drain it, pour it FULL of diesel, and check back in a month.

The diesel flush can be dumped into an older cat (or my 5.9 Cummins)

Talk about waking an engine up,......

Regardless, that engine should get TWO lube oil changes, if it's that musty / rusty inside,.....get the damned cumbustion ACIDS gone.

Luck

GTC

Well damn... Never mind.

Hell Bart. I was gonna call you and then I recognized that damn phone number!! I posted that I was gonna call you and then I had to delete the post!

Jordan

Jenny's a bitch but if you wanna talk to her... Be my guest.

That diesel/oil combo also works great for spraying down concrete form boards. Lots of good suggestions here Rob. But I wouldn't drive it with diluted oil.

Sean:

I assume that is your jeep in the photo. Care to tell us about it? You seem to know your stuff too. I''m hoping to have mine running within a couple weeks. I've got a guy wiring it for me (I'm not smart enough). I've got a high compression after-market head I want to put on it. 'Cept the after-market head does not have the coolant inlet hose to the head like mine does. I think that allows the water to heat faster. Does it matter?

Jordan

Sorry Jordon. I-net photo I found to see what you were dealing with. It is/appears to be the same as a customers vehicle we get from time to time. 41-43? Willy's. Not sure on the inlet hose question. Does it(current/original) have an outlet too? Heater hose fittings? Looking at some more internet pics all I see is the upper rad hose outlet and possibly a 3/8 pipe female at the front or back on the sides, one on top rear drivers side.


What brand of head is it? Maybe I could find some pics and give you a better opinion. Main thing would be water flow to the radiator, any others could be plugged or used as needed.

Sean:

I figured out the water port in the front. It's a bypass to allow for faster heating of the coolant. Your photo shows it on that boss in the front with the plug in it. The Kaiser head does not have the coolant bypass, but it doesn't matter---unless you need it to warm up faster.

Thanks,


Jordan

Not like we are in -40 temps like the others hear.

By-pass does help to distribute coolant in the block and heads before t-stat opens. No hot spots that way. But if the original design allows enough flow, so be it. Feel free to PM me if I can help you in the later weeks. Sack time now, got heavy chores in the mornin.

Had the same thing happen on a IH Cub tractor, flat head, one valve stuck open/up. I had to pull the head off, so I could force it back down in order to use solvent/penetrating oils to free it up. I couldn't get it back down from the side cover. New head gasket and it was back in bid'ness.

Well, she won't free up. Pulling the head this afternoon. Soaked her in Kroil and Freeze Off. No luck. Gonna pull the head, tap her down gently and see if we can move 'er up and down and break 'er free. While we're at it, I'll use it as an excuse to install a Kaiser Super high-comp head.

Can valve seats be recut while the engine sits in the vehicle? (flat four). I've got rust damage on all seats. Two will prolly have to be recut. The rest can prolly be lapped. Valve man is coming for a look-see on Friday. Damn, I sure hope I don't have to pull the engine. Hoping he has a jig that lets him cut the seats without pulling the engine. (Its a jeep L-head 134 Go Devil). My fault. I let rain water into the spark plug holes and now I am paying the price.

Jordan

Yes,....piece of cake.

GTC

Crossfire:

I assume they have some sort of jig that you bolt to the head and power it with a drill or some such thing. I presume my valve guy has one.

Jordan

If I remember correctly, the tool fits down in the valve guide and is done the same way as if the engine were out. Same deal with OHV setup. He might find that the valve guides need replacing which should be an easy job also.

Good luck.

No "jig, no "bolting"

Goodway (among others) has expanding pilots that co-ax in the guide, and carbide cutters that slip over the pilot.

A GOOD hand can power them by hand, or you can attach a drill motor.

This tooling was common fare, back when the flathead was the rule, rather than the exception, and "In Frame" overhauls were common..

I'd venture the seats that you THINK need "cutting" would deliver fine service just lapped.

You're win-win regardless,.....and if your "valve Guy" tells you you need to pull the engine , he's a confused idiot.

GTC

Thanks guys. Really appreciate your expertise.

Edit,....wrong valve tool co. name,....

Its NEWWAY,....not "GoodWay".

Like Cross said, lapping probably would do it. That is done with a little valve grind compound and a suction cup on the end of a round handle.

Nothin to it.

Thanks guys. Good to have such expertise on this site.

The fact that "Clearances" were quite a bit roomier, and the "Marine Bearings" of that day were WAY more tolerant of particulate debris in the engine's oil,.....does NOT mean one should behave like a swine.

"Caulk" the ports individually with clean Rags or Paper Shop towels, and try and be REAL meticulous about wiping off all residual grinding compound, prior to reassembly.

Make yourself a "Valve Stick" and keep track of who goes where, in terms of Respective holes.

You ARE going to need a spring compressor, and you'd damn sure better plug all your oil raceways in the valve gallery ,....prior to srarting the "Knockdown",.....a lost keeper battering in the wrong area is no joke ( even though they'll mostly just disappear, you're still going to be SHORT one keeper).

I make up alla' my gallery plugs beforehand, with stout twine or wire attached to whatever I'm using,....I don't want little chunks of rag zooming around inside, either.

GTC

Jordan.....What Cross said. Great advise from someone who has been there, done that. You will most likely be surprised at what a little lapping will do. Best of luck, keep us posted later.