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Quadrille in JB · 08-09-2020, 13:35

Thanks for all of your help in advance, I searched and read a thread on this but it was hijacked to another topic and never answered the question.
Guys and gals,
The boat is an Endeavor 37 with a 51 hp Perkins 4-108 that has lived in fresh water most of its life up until the last 2 years.
I'm in the process of removing the cylinder head from a Perkins 4-108 that had a diesel runaway due to leaking seals in the injection pump. The crankcase filled with diesel fuel up to the point where it entered the combustion chamber and blew the head gasket.
I have removed all of the items from the head including the rocker arms and all head bolts but...the head won't budge. Two of us have looked carefully all around the block and there is nothing holding it on. I've soaked down the studs with penetrating oil for several hours.
The starboard side of the head where the studs are bathed in oil shows a slight movement when prying up on it but the dry port side doesn't budge.
We're trying to get the boat running to put it on the hard out of harm's way for hurricane season here in southeast Florida.
I'm really at my wit's end (doesn't take much anymore) on trying to get this thing apart so I can do a valve job and re-assembly.
thanks,
Bill in Jensen Beach

sandy stone · 08-09-2020, 13:49

Can you turn the engine by hand? You would think cylinder compression would break the head loose. But you might have to put the rocker arms back on to open the valves on the cylinders not on a compression stroke..

rbk · 08-09-2020, 14:06

If you have a chain hoist put a spreader in the companionway and slowly pull it off. Get a flat blade in one corner to break the seal. Hope that helps.

Quadrille in JB · 08-09-2020, 14:46

Good ideas,
I had thought about using compression but unfortunately the injectors are already in the shop awaiting rebuild.
The lifting idea is one that I haven't thought of. I'm concerned about the strength of the coach roof though. I'll check it out tomorrow.
thanks for the ideas.
I'm going to try a thin blade tomorrow morning to see if the penetrating oil had helped any. And then I'll move on to the next idea.
thanks

rbk · 08-09-2020, 15:37

You can use a block and tackle but a chain hoist works better. Coach roof should easily support the full weight of the engine and then some. The head is most likely just sealed to the block with old head gasket. I put mine under tension with the hoist and used a flat edge to break the seal, once that went it came off easily.

**Madehn** · 08-09-2020, 15:45

old school but get a large block of wood on the head and hit it a solid blow with a 4 lb sledge-- do this after you have put some tension on it with the block and tackle-- make sure that there are not some additional bolts in the center holding it on-- actually check the manual and count how many you have taken out-- sounds real silly but not as sillyt as i felt after beating on a car engine for two days then discovering that there were two hidden bolts.

Cheechako · 08-09-2020, 16:00

IIRC there are a couple of guide pins? I like the hoist idea. 4 x 4 across the companionway..? Put pressure on it, leave it overnight if necessary.

Quadrille in JB · 09-09-2020, 04:32

Thanks again for the great ideas. Keep them coming.
This morning I'm packing up my chain hoist, some small chain to connect to the head, a 4x4, and a 4 # sledge with wood block, my oxyacetylene torch, and a big crowbar.
First I'll try the crowbar (gently) and thin blade to see if the penetrating oil has done any good.
Then I'll hook up the chain hoist and beat it with the block and sledge.
Then, if still needed, I'll heat the studs red hot. If that still doesn't work I'll try and double nut the studs to remove them, I've also got a Snap-On stud removal tool. Then I'll weld a nut to the top of a stud to see if the studs will come out without snapping.
Last ditch effort will be to try and remove as many studs as it will take to release the bind between the studs and head.

oleman · 09-09-2020, 10:43

You have stumbled across a major issue with head studs. I call it rot rusting to the part being held down. Possibly heating and attempting to remove some studs will help. It's not the head being stuck to the engine its the head being stuck to the studs. I have found that a ratchet hoist is a great tool for separating and lifting frozen objects because the hoist is very slow so the operator has very good control of the amount of lift being provided.
I have used a 6T and a 1.5T CM ratchet hoist in disassembly operations.

Good luck with your project.

racer1958 · 09-09-2020, 10:50

Have done various diesels with heads that will not budge. As mentioned above, the studs are the culprits.
Double nut them and pull them out, they are rusty and binding the head down. You will not break the stud. Impact tools are your friend here.

Quadrille in JB · 09-09-2020, 13:54

Olelman hit it right on the head. Studs were rust bound. I used a ratchet come a long to put lots of lift pressure on the head and then started beating on it with a 4# hammer and 2x4 pt. Nothing happened until I used a steel chisel on the close pry points which started movement. 2 hours and a lot of beating later the head released from the rusty studs. I tried locking the nuts but I was only able to remove 2 studs.
Thanks for all of your great ideas and support
Bill in Jensen Beach

rbk · 09-09-2020, 14:15

If you plan on taking it to a shop to get new valves seated and the head cleaned (recommended) make absolutely sure they understand that they cannot take the face down at all or they will owe you a very hard to find new head. Make them put a bright easy to read note on it before they take it or it may end up happening anyways. When I did mine it cost around $70 usd for an overnight pressure bath and new valves seated. They would have swapped out the valve guides for another $30 if they weren’t like new already. This was at a performance auto shop and not some back alley mechanic and was worth the money. Came back ready for paint.

billgewater · 09-09-2020, 15:19

Good to see success.
I have a possibly related question. I have seen gasket leak additives in the auto shops. Made by various companies promising all sorts of success for leaking head gaskets. I have never used these products but I just might carry some for an emergency.
My question is, do these sealants make it harder to remove an engine head?
Are there any secondary issues involved with these products?

Cheechako · 09-09-2020, 15:37

Quote:

Originally Posted by rbk

If you plan on taking it to a shop to get new valves seated and the head cleaned (recommended) make absolutely sure they understand that they cannot take the face down at all or they will owe you a very hard to find new head. Make them put a bright easy to read note on it before they take it or it may end up happening anyways. When I did mine it cost around $70 usd for an overnight pressure bath and new valves seated. They would have swapped out the valve guides for another $30 if they weren’t like new already. This was at a performance auto shop and not some back alley mechanic and was worth the money. Came back ready for paint.

Curious, why cant the head be surfaced?