Difference between revisions of "Engine oil leaks"

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New plan to replace injector pump O-rings: other folks have replaced these O-rings by removing the governor body from the pump without removing the pump or the exhaust manifold by removing the copper lines that block access, and then replacing the O-rings. A pic of the disassembled body is [[Image:Perkins_4108_inj_pump_O-rings.png|here]]. As of 23-Feb we are pretty much at the point of removing the bolts that hold on the governor body. Those bolts have an unusual star-shaped pattern. The way forward is clear.
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New plan to replace injector pump O-rings: other folks have replaced these O-rings by removing the governor body from the pump without removing the pump or the exhaust manifold by removing the copper lines that block access, and then replacing the O-rings. A pic of the disassembled body is [http://sailing.mit.edu/mediawiki/index.php/Image:Perkins_4108_inj_pump_O-rings.png here]. As of 23-Feb we are pretty much at the point of removing the bolts that hold on the governor body. Those bolts have an unusual star-shaped pattern. The way forward is clear.
  
 
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Revision as of 10:35, 24 February 2013

Thanks to all of you who have helped work on the engine, spending quality time practicing novel yoga positions and sampling various 'eau de diesel' aromatic and make-up applications. 23-Feb-13 work party: Eyal Dechter, Denise ____, Dan Lockwood, Matt Wall, Scott Dynes


Task List

(As of 17 Feb 2013)
All these steps need to be documented (i.e. take pictures, label parts in plastic bags) so we know how to put everything together and don't have any left over pieces. Be sure to seal openings left by removed hoses/covers so no dirt will get in.
- Remove exhaust system aft of engine. Remove fresh and raw water pipes from exhaust manifold/heat exchanger. Clean things. This can be done now. (Completed 23-Feb)
- Drain engine oil (using oil pump from pavilion). Remove oil hoses from from transmission and lube oil filter. Clean things. This can be done now. (Completed 23-Feb)
- Remove alternator belt and alternator. Clean things. This can be done now. (Belt removed 23-Feb)
- Remove pulleys on front of engine, remove tubing for raw water pump. Remove timing gear cover BEING CAREFUL TO NOT DAMAGE THE METAL LIP SEATING THE FRONT OIL SEAL OR THE COVER FLANGE. Remove raw water pump from cover (will be rebuilt when have gaskets). Replace timing gear cover to cover opening; tape raw water pump opening. Clean things. This can be done now. (Add-on pulley set and raw water pump removed 23-Feb)
- Drain oil from transmission (using oil pump from pavilion). Disconnect oil hoses from transmission to oil cooler, disconnect mechanical linkages. Disconnect propeller shaft. Clean things. This can be done now. (Completed 23-Feb)
- We will remove the exhaust manifold/heat exchanger; we will need to remove many of the copper fuel injector tubes to make this less painful. Remove needed copper tubes. Remove exhaust manifold/heat exchanger. Clean things. This can be done now. (Change of plans. We will not remove heat exchanger; we will remove copper core and clean as needed. Started 23-Feb.)

The above tasks can be broken down into front of engine and rear of engine; removing the manifold is a 'both' job. I think it most effective if two folks work together, so it is possible (and desirable) to have two teams of two working on the engine at once. Removing things will require tools which I expect are currently on the boat. The exception could be the nut holding the pulley on the crankshaft; I will make sure we have the appropriate tool. This work will be dirty, and you will bump your hands into cold, hard, sharp dirty metal. I've heard that used handball gloves make an effective glove for working on diesel engines; I will likely show up with a pair or more if I can find a source of used gloves (does MIT have a handball team?). Wear clothes and a hat that you won't mind getting incurably filthy.

After we get the engine parts:

- Rebuild the raw water pump. This can be done in the comfort of someone's basement.
- Remove the linkages from the fuel injector pump. Remove the cover of the pump, and replace the O-rings on the throttle and cut-off spindles (there are descriptions of how to do this on the internet; read these first). Replace the cover.
- Replace the fuel lift pump.
- Swap out the lube oil filter assy for a new screw-on version - might need to move the present oil filter assy base.
- Remove the transmission, jack up the rear of the engine, remove the flywheel cover, the flywheel, and the rear crank oil seal. Replace the oil seal and reassemble everything.
- Remount the existing Racor primary fuel filter and the new secondary fuel oil filter where they are accessible from inside the cabin under the stairs. Replumb fuel system.
- Replace raw water pump on timing cover, replace timing cover. Replace front oil seal. Replace pulley. Replace alternator and belt.
- Replace exhaust manifold and cover. Replace pipes. Replace exhaust system aft of engine.

And that's it!


New plan to replace injector pump O-rings: other folks have replaced these O-rings by removing the governor body from the pump without removing the pump or the exhaust manifold by removing the copper lines that block access, and then replacing the O-rings. A pic of the disassembled body is here. As of 23-Feb we are pretty much at the point of removing the bolts that hold on the governor body. Those bolts have an unusual star-shaped pattern. The way forward is clear.


As of the close of the 2012 season, the engine leaks oil - both lube oil (way too much) and fuel oil (more than we'd like). The plan during the early spring push is to deal with all these problems and more:

Lube Oil leaks

We will be replacing both the front and rear crankshaft oil seals on the engine. The front seal seems pretty easy and straightforward; the rear seal will require dismantling much of the exhaust system, removing the transmission, flywheel cover, engine flywheel, and other pieces. Oh, the rear engine mounts are part of the flywheel cover, so we will need to elevate the engine. This process was documented by another sailor at [1]. Parts (mainly gaskets) are available online from a vendor in England ({http://www.parts4engines.com/index.php?main_page=product_info&cPath=39&products_id=263&zenid=cbb906f8c5b0468c8f2444df6e3a4999]) or from Foley Engines in Worcester, which seems a specialist in Perkins 4.108 engines[2]. They have so far been unresponsive to price quote requests; I am persistent and will get the quote (and likely the parts) from them.
It might be the case that the real leak is not caused by the front oil seal but the gasket for the timing cover; this will be replaced as well.

Fuel Oil leaks

Both the lift pump and the injector pump leak. The lift pump is 'easy' to get at and will either be replaced or rebuilt. Replacing the requisite O-rings in the injector pump is best done by removing the heat exchanger, and at the moment that is the plan. This will also allow us to change the orientation of the cut-off lever so that we can pull the T-handle to shut off the engine.

Filters

The lube oil filter is in a difficult spot, and is next to impossible to replace without dumping a fair amount of dirty oil over the engine an into the bilge (the design requires the removal of a metal bell; the filter is a paper cartridge inside). The primary fuel oil filter is accessible at the bottom of the stbd cockpit locker, close to where the ends of the emergency tiller bang around. The secondary fuel oil filter is much like the lube oil filter, inconvenient and messy (it's not been changed while MIT has had the boat). I'm going to replace the lube oil filter with a standard spin-on unit in a more accessible location. The two fuel oil filters I'm going to move so they are accessible from behind the steps inside the cabin, and replace the secondary fuel oil filter assembly with one that has a spin-on unit with a clear bowl at the bottom (complete with a drain valve), The time I've been on a boat where the diesel engine has failed was due to fuel contamination.

In addition the usual pre-season things will be changed, like the raw water pump impeller, filters, etc.

I believe that in the end we will have a reliable engine that is leakless (ha!) and will be much easier to service should the need arise.

Other things that would be nice but not necessary:

  • Relocating the lube oil stick. This can be done in theory by bending the tube; there may not be a better place to put it.
  • Removing the engine from under the stairs to perform these tasks. This would make everything so much easier but we'd have to build special rigs to make it happen. We'd also have to assure that the alignment with the prop shaft is replicated when we put it back.
  • Having the fuel injectors cleaned. This would seem to be the right time to do it; we'll be removing much of the injector plumbing. Nothing seems wrong with the injectors, though.

The parts list (i.e. what I asked Foley to quote a price for) - the parts numbers are from the engine parts list on the wiki ([3]):

Update 15-Jan-2013: Foley was less than unresponsive regarding quotes. Trans-Atlantic Diesels (http://www.tadiesels.com/; ask for Sheri Moon) was quite responsive and helpful; their prices were much higher than the folks at http://www.parts4engines.com, who were also very responsive.

  • A PTFE replacement rear oil seal - replaces 36883115 Seal - rear end oil (set of 2)
  • 36826114 gasket - REOS housing (might be part of your kit)
  • 0730098 seal- front end oil
  • 36813145 gasket - timing case
  • 36826122 gasket - flywheel housing
  • 36867115 gasket - flywheel housing
  • 36857107 gasket - flywheel housing
  • 0490724 gasket - cyl. head cover
  • 36862517 gasket - oil filter head
  • 0500006 woodruff key for pulleys on crankshaft
  • 0490656 gasket - exhaust manifold (2)
  • 24860167 cover (rubber cover on end of water heat exchanger/exhaust manifold)
  • 24865264/24860166 cover (rubber cover on end of water heat exchanger/exhaust manifold)
  • 0490785 gasket - water pump
  • 0460038 impeller - water pump
  • 0730110 plug - water pump
  • 36821503 gasket for mounting raw water pump on timing cover adapter plate
  • 33825411 (need 2) - gasket for mounting raw water pump on timing cover
  • 3685R008 gasket- lift pump (4 bolt)
  • U5MK0160 repair kit - fuel inj pump (we are only looking for the o-rings for the throttle and cut-off spindles of the hydraulic version; don't have separate part #s)
  • A replacement 4-bolt lift pump
  • A spin-on secondary fuel filter adapter kit (thinking about a Racor 120RMAM - ~$70-$130)
  • lube oil spin-on filter adapter kit