Yanmar 2GM20f oil leak

Dave_Rolfe

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I have an oil leak on my engine that I have identified as the timing chain cover gasket. In a thread from 2007 a respondent put the following advice

'Have a look at the bottom of the timing gear cover, right at the front of the engine. Any sign of oil at the bottom of this means the gasket is weaping. If this is the case and the leak is very minor, it can be cured by getting the joint area with the block very clean and degreased and applying appropriate sealer (Thiokol do suitable products: http://www.polyspec.com/technologies/THIOKOL.htm ) externally over the joint. Done properly it will probaly be more reliable than replacing the gasket and a lot less hassle. The same process can be used for any small leak at an engine joint that is unlikley to be disturbed for years'.

I've never heard of Thiokol and cannot find a UK supplier or advice. Does anyone know anything about it or can provide an alternative that can be obtained in the UK. Perhaps someone has overcome the same problem in a different way.

Thanks for you help in advance
 

savageseadog

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There are various gasket products Loctite do quite a few that are easily found at motor factors. I've used Sikaflex on cooling system joints successfully would probably work for that as well.
 

mhouse

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Another good bodge ito have in the get you home box is a tube of mastic sealer that sets underwater. Available from plumbers merchants
 

TeamSpirit

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Not difficult or complicated to replace the gasket which Yanmar have now redesigned to prevent future problems with the timing cover gasket. I replaced mine and completed a full service at the same time over a day.
Would not recommend any bodge it or stick it unless it is a get you home job as you will risk loosing most of your sump oil into the bilge if it were to fail.
 

zekingpo

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Not difficult or complicated to replace the gasket which Yanmar have now redesigned to prevent future problems with the timing cover gasket. I replaced mine and completed a full service at the same time over a day.
Would not recommend any bodge it or stick it unless it is a get you home job as you will risk loosing most of your sump oil into the bilge if it were to fail.

Hi TeamSpirit.

Sorry to bringing this old thread back to life but I've been looking for advice from people who had done this job after noticing a small leak around the same gasket on my Yanmar 2gm20f last weekend.

I'm no mechanic but I can manage to replace an impeller ou change a strap. Is that a job that requires a lot of specialty tools or skills? I found the description of the steps in the Shop manual (http://boatinfo.no/lib/yanmar/manuals/1gm10.html#/98) but it isn't necessarily language I am familiar with.

Thanks for your input!
 

TopZ

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Hi TeamSpirit.

Sorry to bringing this old thread back to life but I've been looking for advice from people who had done this job after noticing a small leak around the same gasket on my Yanmar 2gm20f last weekend.

I'm no mechanic but I can manage to replace an impeller ou change a strap. Is that a job that requires a lot of specialty tools or skills? I found the description of the steps in the Shop manual (http://boatinfo.no/lib/yanmar/manuals/1gm10.html#/98) but it isn't necessarily language I am familiar with.

Thanks for your input!
About to do the same gadget replacement. Any tips or advice?
 

vas

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check carefully the yanmar manual, explains what's involved.
Not THAT straight forward, especially in an F model as you have to remove the high pressure pump before attacking the timing cover and it fouls on the heat exchanger (and you have to remember to move the governor to circa half throttle in order to go through the mounting gap and pull away...)
No special tools needed other than iirc an extractor to remove the crank pulley. The rest I think are 10mm (or 13mm) hex. Mind it's 3yrs since I've done it on mine and memory's fading.
If you go through all that, do remember to check and replace the governor shaft o-rings as they also leak (mine badly!)
fwiw, couldn't find the gasket alone and quickly, so cut my own with the right thickness gasket paper, took some time but was fine.

V.
 
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