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High oil in 4.107

Magnus Hultin

New member
I suspect I have diesel in oil sump after noticing raising level on dipstick. No indication of water emulsion since no creamy or milky appearance. Oil is clear (allthough towards blackish) and significantly thinner than normal. I have emptied the sump, replaced lift pump and filled with new oil. After test run of two hours level still raising why I suspect injection pump needing overhaul. Current pump has been in service approximately 20 years without service.

The boat is a 37 feet sailboat in summer only usage on Swedish west coast.

Are there any tips on precautions in front of dismounting, not to mess up engine timing?

This is a well known marine engine among servicemen, those of age, but I am seeing a decline in active mechanics who have actually been doing this kind of work. I may need to turn to workshops for tractors and agricultural equipment.

Thankful for any advice, or thought on the diagnosis for that matter.

Magnus Hultin, Onsala - Sweden
 
Most likely the seal on the front of the pump.
The 4108 is used in farm equipment, probably the 4107, too. So a farm equipment dealer is one place to look. Best bet on timing is talk to a shop the rebuilds injector pumps and get their recommendation.
Do you have a shop manual? You should be able to download one online. Maybe one for the injector pump, too.
You need to get the engine on #1 TDC (marks on the gear train and maybe on the flywheel), then there should be a line scribed on the pump mounting flange and a matching one on the engine. There should be marks on the pump for #1 alignment. As long as the pump is removed and reinstalled matching the alignment marks it should run.
Parts 4 engines has a rebuilt pump: https://www.parts4engines.com/perkins-4-107-dpa-injector-pump-hydraulic-governor/
Lepke Oregon USA
 
Thanks Lepke


I have the original workshop manual which has been kept in good condition since 1967 by the original owner (my father) and I have downloaded later copies covering 4107M and 4108M. Have not been able to find a good workshop manual for CAV DPA injection pumps though. I am aware of reman pumps being available from Parts4Engines, have shopped other parts form them in the past and appreciate their service.


As far as I have understood from reading the timing sections of the manuals, at #1 TDC the key for the crankshaft pulley is at the top of its periphery, but I have yet to understand how to distinguish between compression cykle and exhaust cycle.


My understanding is the 4107 pump drive gear has a master spline so it will only fit one way. If I secure the engine does not rotate while the pump is out (it won´t) I should be able to position the spline the same way while mounting as it came out.


One question; there is a scribed line on the fuelpump mounting flange and the mating mounting flange on the engine block which should aligning for correct timing. This line is made in factory after adjusting timing. If I recieve an overhauled pump my understanding is this alignment will be lost, does this mean I have to adjust the timing "the hard way"...?
 
British machining about the time of your engine required a lot of hand fitting and filing. Not like today where you can buy a part, replace it and go. You'll see if you read about replacing the pistons. If you're rebuilding the pump then the scribed line works. With a new pump, it's a little like a distributor on a gas engine. The new pump should run, but the exact timing will be different. In a shop you set it on an engine dyno. If you know the wide open throttle rpm in gear, you can run the engine in gear at wot and move the pump slightly until you achieve that rpm. I don't remember the degrees on that engine, but fuel is injected before TDC. If the pump is too advanced the engine will knock hard and run poorly. If it's to late, you loose power and the rpms go down. If it knocks hard at startup, seems like it wants to fight the starter, or tries to run in reverse, it's too advanced. If it barely runs, has a quieter knock than before the rebuild, then it's retarded. Don't ask the direction, I don't remember. (Even with the scribed line, it's hard to be perfect)
If you rebuild your own pump, be extremely clean. Most pumps have close tolerance parts that can be damaged by a paint chip or grain of sand.
Compression or exhaust stroke: With the valve cover off, turn the engine over slowly and watch the rockers. As you approach TDC on the exhaust stroke, the exhaust valve will be closing. At TDC the intake rocker will be tight because the valve is opening for the intake stroke. On the compression stroke, starting about 180° before TDC both valves will be closed and the rockers loose. At the top of the compression stroke the rockers will still be loose because both valves are closed. Loose is the amount of valve lash setting.
I've been rebuilding diesels, mostly bigger engines for about 50 years. My preference for injector pump engines is to have the pump rebuilt by a shop. They have the test equipment, know it's correct, and then you have the same pump. Having a shop rebuild a pump is usually more than buying an off the shelf rebuild.
 
Thanks again Lepke, Your are true scholar!

I was in contact with Parts4Engines.com and they can rebuild my pump and return it to me, it normally takes one week excluding logistics. Hopefully this means I will have the scraped line to work which will save me loads of precision adjustments in horrific cognitive positions. Port side of my engine is a nightmare to reach, something I experience every autumn changing oil filter. While shopping from Parts4Engines I may buy one of their oil filter conversion kits which will simplify this work tremendously given it fits the available space on my port side.

https://www.parts4engines.com/perkins-4-107-oil-filter-conversion-kit/

/Magnus
 
I now have the boat on land and am in the process of dismounting the CAV pump.
Can someone advice on which allen tool to source to access the mounting bolt on the inside of the injection pump, between pump and engine block?
I cannot reach it easily for a measurement but I assume it is imperial size rather than metric and it looks to be either 1/4", 7/32" or 3/16".

Does anyone have a record or advice?
 
OK, identified the Allen size to 7/32 which I could only find in a multi key tool, so I dismounted the tool cut a straight section of the 7/32 key and fit it in a 6mm socket with extension. It came off fairly easy even though my body is unused to these working positions.

The really tricky part was the nut right under the pump. Not only did it mean working with no visibility (had to lean over the engine from starboard side and work form above), this nut also allowed very limited access and movemnt per stroke for a combi spanner. This is excercise You don´t want to do every day.

In any case, the pump is loose and will go to a local pump shop for overhaul. I documented every step with pictures (including the angular position of the tooth wheel of the drive shaft on the pump) and written notes and tape marking of each loose part ( bolts, nuts and fuel pipes). The drive shaft had two square teeth sections, one of each gender, separated by 180 degrees, so I feel safe it can only go back in one position. The scraped line between engine to pump flanges were sharp and clear and I have good pictures of this to.

I have good hope of getting it back on the engine with fairly correct timing.
 
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