stuck engine

[jharding]

Hello, I need some ideas. Today I found my perkins 4-236 with seawater in oil and one cylinder. What a shock. I had run the engine a month ago and all was fine. I surmise that water backed up the exhaust, not exactly sure how that has happened. It’s very rough in the anchorage with 20-30 knot winds every afternoon. Here is the question how do I get the engine to turn over. I have taken out the injectors and got all the water out of crankcase and cylinder and drained the waterlift muffler. I squirted some pb blaster in all cylinders. Put a socket on the end of the crank with a pipe on the breaker bar, can’t budge it either direction. I heated up some ATF on the stove to 300 degrees and poured it into all of the cylinders. No luck yet, I took off valve cover and checked, all valves have clearance except the cyl that had the water, I backed off the adjustment on the exhaust valve and hit all of them with a hammer, all spring back. I siphoned out the ATF and heated again this time I mixed in acetone in a 1 to 1 ratio, then put this weasel piss into the cyl. Still not coming loose. I’m worried about putting too much pressure on the crank nut and hurting the end of the crank. I’m getting ready after weasel piss sits in overnight to try to put air pressure into the froze cylinder. I was wondering if I could plumb it up to the injector or if I should try to hold a plug into the injector hole. I also tried an impact on the crank nut, no help, I took starter out and tried prying on the ring gear, no movement. I’m good at getting stuck things apart, shock and heat is my friend, not helping here. I hope the air pressure on the piston will get some movement. I was also wondering about putting some vinegar in the cylinder to break up the corrosion, or some other chemical. What are your thoughts.

[Lepke]

The rings (usually cast iron) are rusted to the cylinder wall. Sometimes you can put a socket on the crankshaft pulley nut and with a breaker bar and cheater on the breaker bar, you can break it loose moving the bar back an forth. I don't think air pressure will do anything.

What I use is Kearney Rust Cutter. It's made for transmission linemen to break loose rusted nuts and bolts while hanging from a helo. Linemen don't have time to to mix lard and kerosene or whatever formula gets posted here. It contains light oils and a mild acid. The acid dissolves rust but doesn't hurt good metal. It works in a few minutes or less if you can get enough on the rings. Available on ebay or large electrical supply. Depending on the engine size and effected cylinders, I use about a half can plus.

[marcjsmith]

marvs mystery oil, beaker bar and ring gear got my 4108 to move after 8 years. took a few weeks though. every time id pass by the engine bay lean in and try to move it...

[jharding]

Thanks for the reply's, I will try to get the Kearney Rust Cutter, however I am in Dominican Republic and getting many things is hard or impossible. I was wondering what else I could use that would be a common chemical

[LittleWing77]

Hey J,

This is probably THE most useful thread on a seized engine that I've ever come across. Lots of super suggestions and support. From about a month ago.

With patience and time, hpeer was able to get it to crank. Fingers crossed that you will be able to - too.

4JH4 Seized
https://www.cruisersforum.com/forums...ed-252586.html

Warmly,
LittleWing77

Oh, and I see Wottie (Wotname) is lurking. Whatever he says. Wottie is King!

P.S. Personal aside: What IS it with these Perkins engines? This is the third recent Perkins hydrolock/water-in-engine thread that I've read!!!

[EngineerRetired]

I've ran into some VERY stuck engines and damaged the crank bolt trying to turn it. Best solution I've found is to remove the belts and put a chain wrench (https://www.amazon.com/MAXPOWER-24-I...NsaWNrPXRydWU=) around the harmonic balancer (crank pulley) with a long cheater bar. You can get some SERIOUS torque on it doing this.

[jharding]

thanks for the link littlewing, I tried searching but did not use seized in the search and did not find much info. Hopefully today the engine will turn over I am going to pull out my gear driven raw water pump incase it is holding back engine as someone else suggested. Thanks for everybodys helpfull Ideas. this just makes me sick, it is such a good engine.

[LittleWing77]

Originally Posted by jharding

thanks for the link littlewing, I tried searching but did not use 'seized' in the search and did not find much info.

You're most welcome!

I *did* use 'seized' in my search and I STILL had trouble finding that thread - and I already knew it was there.

No worries. It's a useful thread and I wanted to find it. Now I'll remember the title going forward.

Originally Posted by jharding

Hopefully today the engine will turn over. As someone else suggested, I am going to pull out my gear driven raw water pump, in case it is holding back the engine.

Thanks for everybody's helpful ideas. This just makes me sick, it is such a good engine.

We'll keep fingers crossed for you and do let us know how you get on.

Remember, though, a couple of people have said it took a week or so to free things up, so if it doesn't crank today, it may yet!

Hang in there!
LittleWing77

[jharding]

Thanks everybody for your reply's and support, I have given up on our little trip for this week. This is going to be a longer haul than I first thought. I have ordered the Kearney rust cutter and also some archoil rust remover that I have used externally on some motorcycle parts with amazing results. Yesterday I put in some marvel mystery oil, still no movement. I have the time to wait for these products to do there job, I'm not the most patience person sometimes, I will slow down and wait, I really don't want to pull the head, I have ordered a full gasket set incase I need to. I need to get some shock into the piston to get it to free up, any suggestions?

[Lepke]

If your goal is to not rebuild the engine, be careful of too much torque on the crank nut. If the rings grip isn't loosened, you may crack the rings and lose even more compression.

[jharding]

Thanks for everybody's reply's, I have been keeping cylinders full of weasel piss and/or Marvel mystery oil, still stuck solid. I am waiting for some other chemicals to come, hopefully being patience and with other chemicals she will come free next week. Being in Dominican Republic things take a week or two longer, I'm getting more patience as I slow down in the cruising lifestyle living in other countries. A little nervous with hurricanes coming and no running engine.

[skipperpete]

Originally Posted by jharding

Thanks for everybody's reply's, I have been keeping cylinders full of weasel piss and/or Marvel mystery oil, still stuck solid. I am waiting for some other chemicals to come, hopefully being patience and with other chemicals she will come free next week. Being in Dominican Republic things take a week or two longer, I'm getting more patience as I slow down in the cruising lifestyle living in other countries. A little nervous with hurricanes coming and no running engine.

There is an often unnoticed secondary issue from cylinder flooding during the early phase of freeing the pistons. The water in the oil pan had to get there by leaking past the pistons, down the liner, over the crankshaft and then into the oil pan. Sometimes no crankshaft/bearing damage occurs but sometimes the shaft gets locked up as well as the piston. Hopefully the regular doses WP and MMO are dripping onto the crankshaft and keeping it free of corrosion.
The only sensible path forward is to remove the head as you mention, an engine with ring and liner corrosion can never really be trusted.

[hpeer]

Years ago I bought an old Volvo MD-7A sitting under a tarp. The guy sold it for a song and swore on his Mothers grave it ran when pulled out and still turned over. His price was less than a starter or injector pump so I just grabbed it and ran.

At home it would not turn over. I initially got some slight movement but it then froze solid.

So I pulled the head. The #1 cylinder had some slight corrosion visible. I soaked it wih this and that for a while, a week or two. Being a very patient and deliberate person I whittled down a short bit of 2x4 to fit onto the piston and gave it a sharp whack with a 16oz hammer. It popped loose. It now spins easily by hand.

If I don’t strip it for parts I will someday get it rebuilt as a spare.

NOTE!!!!
I am telling what I did, not what you should do.

[Cheechako]

It must have sat a while?
If it were me, my immediate concern would be to save the engine.
I would already have the head off pronto. Soak the cylinders with Pb Blaster or whatever 'slops your dripper'. Then using a piece of soft wood and a hammer, tap on the top of every piston to shock it.
One hour or less and the head's off.
Even if you broke the pistons loose now, you really need to cycle the engine and clean the rust off the cylinder walls, you can't do that with the head on.