Leaking Simms injector pump

Hello Everybody
I'll get right to it. New here and new to trawlers.
I have a 1985 Marine Trader with a 108 hp Ford American with a Simms injector pump. This pump has oil in it and requires changing.
Now in Jan 2017 injector pump failed and was rebuilt. After re-install engIne cranked right up and ran great. We left St Augustine for Marathon, fl. After arrival I changed engine oil and went to drain injector pump but only got about 6 oz out. Filled with oil (16oz). A month goes by we moved boat to mooring. Checked oil level and down 6 oz. Checked every so often and oil always low, always topped up. I have oil under engine, no visable leaks. Placed oil diaper under pump on top of raw water pump. 2 weeks and oil is low, not a speck on diaper but more under engine, engine oil level is stable. This is a static leak, meaning the engine has not been started in more than 5 months. I can't find any indications of a leak anywhere.

HELP!!!
Greg

the injector is gear driven and the front gear seal could be leaking the injectors oil into the engine itself and if the rear main seal is leaking...

I wouldnt consider either catastophic, just need to keep a daily check on them.

Re read post.mk

EngIne h as not been started in 5 months, engine oil level is stable.

I don't think 6oz of oil will show a difference on your dip stick.

You need to fix the problem or do frequent oil checks.
The main body seal should be available at any pump rebuilding company - maybe under warranty from your recent rebuild. Running the pump with low oil will eventually cause problems. The oil has less time to cool , it may not circulate correctly, and so on.

Have you checked the calibration of your dipstick? They are tractor engines that they just marinized them but did not recalibrate the oil stick. Change the oil and put in the proper, manual amount of oil and then remark the stick. If you put in too much oil it just pushes it out. Any way it can come out.

Have you changed the oil in your injector pump? Has to be done regularly.

The most likely place for an oil leak is the lift pump gasket. Change it and stop almost all the leaks. Also but not as likely, the fuel injectors, where they contact the block, can be loose and leak oil.

There is a mod you can do to the vent on the injector pump that stops all the overflow from it. Also, never remove the full-level plug, just measure the correct amount of oil.

That's all I can think of now.

Xsbank said:

Also, never remove the full-level plug

Click to expand...

Why is that?

Vent mod

Xsbank
Can you explain vent mod or direct me to information.

Thanks
Greg

Hi Barnacles, because you don't need to. Just measure the oil quantity. If you take out the level fill, you will drop it and a bilge ferret will get it and now you are hooped, it has a weird thread and its a weird size.

You can even use a small ice-maker valve from a refrigerator with an adapter of the correct thread size, so that you never have to remove the drain plug either. The threads in the body of the pump are soft and eventually they will wear out and the plug will not seal any more. Then you have another small but critical repair to do.

Most Simms have a pipe that is connected to the side of the pump with a banjo bolt. If you look at the filler cap, it has probably already been drilled with a small breather hole. If not, take it off and drill a hole with about an 1/8" drill in the middle of the screwdriver slot, then take off the drain pipe and put the banjo bolt back in with a copper washer, then throw the pipe away. No more catch cans, no more drooling in the bilge.

Interesting. Thanks for the info, I was unaware of the drill mod as well.

Vent mod

XsBanks

2 things

1 won't the banjo bolt go in far enough to damage anything inside without being shortened?

2 won't the 1/8" hole in the fill screw alow dirt into the pump?

Thanks
Greg

2 good questions, the washer on the banjo bolt is intended to prevent it going too deep but as I don't have one in front of me, you will have to do the measuring. The po or the manufacturer drilled mine, I removed the pipe and I never had anything adverse. The drilled hole is pretty small...I believe the interior of the pump to be a little pressurized so any dust would have to get in with the engine off. YMMV.

Vent mod

XsBank
Thank you very much. Sounds reasonable, so I 'll do the mod and let you how it works.

Thanks again
Greg