Perkins 4-108 Rebuild

[THATBOATGUY]

It won't fit out of the boat in one piece so I'm having to take it out in pieces.



By myself I couldn't lift the head off of the block with one arm all the way extended so I worked it up in stages with a couple of wood wedges I made.



What a mess! The transmission, bell housing, fly wheel and adapter plate all off.



Up she comes.



The tricky bit is changing from mostly vertical to mostly horizontal. Here she's making the change to come up the ramp to the house top.



The majestic 4-108.



Boomed over to the finger pier.



Hand trucked to the trailer. Getting off of that ancient shaky finger pier was the scariest part of the job!



Safely delivered to the back yard to be striped down to the block. I'm sending the block up to NY to have the new liners pressed in and the cyl head rebuilt. Once it's back here I'll begin the rebuild.

George

[OldRover]

Sorry, I've been offline due to travel (air, not the fun way...). Anyway, I got my rebuilt engine from http://stores.ebay.com/Ozianas-Attic-And-Garage - he said that is the best way to contact. My motor, the core, will be heading back to him on Friday. So there will be one available based on his turnaround. I'm curious who in NY is doing your liners?

[THATBOATGUY]

AgKits.com I noticed on their website that they did cylinder heads so I asked him if they would press the liners in for me as well. $40 per hole is a good deal and since I'll be shipping the head up to them anyway I'll let them do the liners as well. I've done business with them in the past and always been happy with the service. I didn't hear back from the guys in Alabama about the injector pump and injector service so I guess I'll keep looking.

George

[rds]

Just a quick comment from my recent rebuild experience. I just went thru the same process only with my 4JH Yanmar. I brought my crankshaft to the reputable shop referred by “Mack Boring ” . They ground my crank main journals / crank pins to ~ 0.0035 – 0.004’’ clearances. According to manual this is a maximum allowable assembly clearance (manual says: 0.0014-0.0036’’) for my crank. I bought several connecting rods and managed to reduce some tolerances a bit by playing with push rods.
Diesel assembly guidance specifically recommends 0.001’’ clearance per 1’’ of diameter ... the lesser the better. (say in case of 2’’ main journal diameter the clearance between shell and journal should be up to 0.002’’ ) .
All in all my engine’s holds very good oil pressure, it is working quietly ... but am not particular happy about this particular issue... maybe it is nothing serious but
if I did it again I would specifically discussed with machinist the pin, journals diameters and expected assembly clearances … and asked him to grind to almost nominal undersize… and double check that .

[THATBOATGUY]

I'm not sure what you are getting at there. I micrometer my own cranks and double check clearances using plasti-gauge. I had excellent oil pressure with this engine when it was last running so I doubt the crank is going to be a concern. The problem we were having was low compression on number two causing hard starting and oil leaks (imagine that).

Who is good with pumps and injectors? I have not heard back from the guys in Alabama so they have removed themselves from consideration.

I will be sooo happy to be on the other side of the filth. Right now the heat is really slowing me down too.

George

[rds]

My mistake, I thought you was going to do complete overhaul... again in my machinist ground bit more than I hoped for. Once he did that there was no way to revert it back, and there is only one , 1st undersize for my yanmar in marine application! So once he went thru with grinding it is very expensive to remedy. new cranckshaft is $3500 + month in shipping.
(industrial and tractor applications have 3 undersizes , the same part # , crankshaft... just not a marine)
Here is a link to fuel injection service shop
http://www.mackboring.com/
http://www.mackboring.com/recreationalmarine/
They did my injection pump and injectors... looks like they do all east coast.. the only fuel injection shop is located in NJ so everything has to be shipped over there. I am not sure about your perkins but worth to ask. The guy who did my pump looked quite skillful and knowledgeable.

[THATBOATGUY]

Oh OK,

I was confused by the discussion of pushrods and clearances :/

Anyway this is very *close* to a complete overhaul as I'm doing everything but cam bearings and I may end up doing those depending on what I see inside the motor.

- Complete cyl head renewal including guides, springs, valves.

- New liners, pistons, rings.

- New wrist pins, rod bearings, crank bearings.

- Rebuilt injector pump and injectors. (I've got a recommendation for a local shop that I will visit on Monday to see if I want to go with them or not)

As for the crank? If it mics out good there is no reason to grind. As you point out, grinding is a one way street so I can polish it up and use as is. When I go to assembly I make one final check with plastigauge to make absolutely certain that all clearances are within factory spec. It's a pain because it means I'll be essentially torquing all crank and rod bearings twice, but worth the piece of mind.

George

[THATBOATGUY]

One main and one rod bearing. All looked perfect but for ones in the number 4 connecting rod. Those had a fine scratch that I could just catch a fingernail on but the crank itself is perfect mirror smooth. These are confirmed standard size bearings.

George

[THATBOATGUY]

The block and head on their way to New York to the machine shop. They will press new sleeves in the block as well as new valve guides and at least one new valve seat, all new valves and springs. Then ship it back to me along with the remaining parts of the rebuild kit.



George

[THATBOATGUY]

Here's progress on the engine rebuild. We had an earthquake while I was working on it today. That was different.

Looks like we might have a hurricane this coming weekend. Yippie! I get to stop for storm prep now. :/

George