Problem with Perkins 4.108 Fuel Pump

[cburger]

Was connecting the Morse throttle control cable to the armature on the hydraulic fuel pump and in the process of installing a cotter pin to secure the pinion to the armature on the fuel pump, I somehow managed to create an electrical arc so hot it welded the cotter pin to the screwdriver I was using. The only thing I could figure was that I must have made contact with the starter solenoid that is next to the pump. I didn’t give it much thought until I fired the motor up today and now have a really nice fuel leak that appears to be coming from the shaft that is connected to the throttle armature protruding from the pump body. I am wondering if any of the 4.108 pros might have any idea what I “F” ed up. I have the Perkins part manual for this motor and of course the pump in the book is different than the one on my motor, (A lowline). I am hoping it is something simple like a seal that could be replaced without having to remove the pump, a real nightmare. Any help would be greatly appreciated.

[cburger]

Could sure use some help with this please.

[Dynamo1181]

There is at least one current thread running that describes the replacement of an O ring seal on that shaft. Do a search or maybe someone could give you a link to this thread. You will have to remove the exhaust manifold to have easier access to that top section of the pump.
A

[cburger]

Thank you Alan, I had seen your thread from 2010 and followed our Aussie friends insights as to removing the govenor body vfrom the pump. I managed to get ot off without having to take the heat exchanger off, just disconnected a couple of fuel lines to get better access, was stilll a bitch about foru man hours for the two small bolts.

The good news is that it appears that I had nothing to do with this issue. When I removed the throttle shaft one O ring was missing and the other two look worn, don't think that was done with an electrical short.

Did you ever resolve your leak yourself and if so do you recall where you went for the seal kit ? I need a new flange gasket and might as well replace the inner spring and small plastic thingy whist the unit is off the pump.

[Dynamo1181]

I did not do it myself but next time I will. It cost me an arm and leg for a complete rebuild. It those rings should be easily found. If you find a source please advise and I will pick up spares. I would think they are nitrile seals that could be found at most well stocked hardware stores???
With more than 20 yrs on that engine, I have a theory...I always used a throttle return spring on that shaft. I think that the side force from the spring on the somewhat hardened O rings, creates the leak. I removed the spring since it served no purpose in my installation with the control cable. I am also careful not to leave the engine with the throttle hard off against the stop for the same reason. BTW i have had that pump rebuilt 3 times over those yrs for the same leak.
A

[cburger]

Alan considering how hard it is remove the govenor I want to replace seals with the "Real McCoy". Just thought with you being a veteran you might have the parts pak number for this service.

I am also tying to get an exploded diagram of the unit as the litle spring and pin came out and sure would like to know how it assembles.

I deal with Kraft power in upstate NY and they have been very good with parts for the Perkins.

Regarding the why's of the seal failure, I think it is just fair wear and tear and am just happy that it wasn't the pump having to be removed. Boy am I glad I came across your post.

How are you liking your 4.108?

Chris

[Dynamo1181]

I have 6500 hrs on it and love it. It has never let me down. It leaks but I supose all 4108s do. I had the rear seal replaced once and the mechanic cut the seal to fit which is a no no. The first seal lasted 3000 hrs the leak became excessive. This newer seal has gone 1500 hrs and is at the same level of leaking...5 oz in 100 hrs. I have cared for the engine, always changing oil, adjusting valves etc. she purrrs! I burn or leak maybe 1.5 qts in 100 hrs, which hasnt changed since I got the boat with 600 hrs on the Perkins.
A

[cburger]

When I bought the boat the origional 4.108 from 76' was junk, after much research decide to install an 84' lowline that I bought from a CF member. As the motor was out of the vessel I gave it to a mechanic to go over, for GP we broke it down and inspected the inner workings. Put about 2k in new parts as it seemed like the smart thing to do. Had to redo the engine space to accomidate the new footprint. Yesterday was supposed to be a red letter day starting the new "Old " Perkins in the boat that hasn't seen a running motor since 97'. Was a little down when I saw the fuel leak, but feeling much better after pulling the Govenor today and seeing it is obviously the "O" rings.

I will update you regards the info and availabity of a genuine Perkins seal set. Do you have any idea who makes these govenors for Perkins as they might be a source for an assembly diagram.

[cburger]

Pic of the motor.

[cburger]

Forgot to mention as part of the work done on the motor main seals were replaced with Foly's synthetic seal, supposed to stop all leaks in those areas, remaimns to be seen.

[Dynamo1181]

I have the same low line with the Bowman heat exchanger. I have heard mixed reviews on the Foley seal. Let me hear how it goes. I had a friend with 12000 hrs on his 4108. He replaced it with a Yanmar because he had a connection for a new Yanmar for little more than a 4108 rebuild. He never had the head off the 4108.
A

[DeepFrz]

You should be able to get the o rings at a bearing shop.

Also Bill T. has posted that he installed a Walker Air Sep on his 4-108 and it stopped a lot of the leaks and cleaned up his engine room.

[Dynamo1181]

Originally Posted by DeepFrz

You should be able to get the o rings at a bearing shop.

Also Bill T. has posted that he installed a Walker Air Sep on his 4-108 and it stopped a lot of the leaks and cleaned up his engine room.

I looked at the Walker site and from what I saw, I am not sure how it help on leaks. Can you shed some light or provide a link?
Thx
A

[DeepFrz]

Here is one post by Bill. If you have any questions why don't you PM him (btrayfors).
http://www.cruisersforum.com/forums/...sel-16043.html

[cburger]

Originally Posted by Dynamo1181

I have the same low line with the Bowman heat exchanger. I have heard mixed reviews on the Foley seal. Let me hear how it goes. I had a friend with 12000 hrs on his 4108. He replaced it with a Yanmar because he had a connection for a new Yanmar for little more than a 4108 rebuild. He never had the head off the 4108.
A

The 4.108 are legendary as long lived motors, I have actually read about an individual who claimed 32,000 hrs in a marine application. Often the were utilized for continuos duty service like driving refrigeration compressors. One of my engine shop manuals is stamped Carrier Trans Cold Company.