Glue guide in valve cover

[jmargo]

Pulled the valve covers today and one of the chain guides was sitting on the top of the chain. I JB welded it back on. Will that hold or did I use the wrong stuff.

Thanks

 

[WREKS]

I would try to make sure JB weld is not affected by motor oil. If it lets loose it could end up in the camshafts. At least overlap the ends as in the image. Here is a link to a thread where a loose chain guide may have destroyed an engine. Chain guide failure?

 

[tdonoughue]

FYI: FAQ

See the one about whether it is ok in gasoline. They say it is good in all petroleum products.

 

[jmargo]

Thanks. I added a bead of 3M 4200 just in case.

 

[WREKS]

If I remember right, there are detents in the valve cover that the chain guide gets pressed into.

 

[jmargo]

There are detents in the valve cover.

 

[marcham]

Is 4200 rated for those kinds of temperatures ?

 

[WREKS]

I doubt if JB Weld or 3M would stand behind their product used in this way. If the chain guide ever let's loose, it is, probably, only a matter of time before major damage occurs. I would replace it. In this case a mechanical attachment is better that a chemical one.

 

[jmargo]

I doubt if JB Weld or 3M would stand behind their product used in this way. If the chain guide ever let's loose, it is, probably, only a matter of time before major damage occurs. I would replace it. In this case a mechanical attachment is better that a chemical one.

It is held on by some sort of adhesive from the factory. It also rides right above the chain and with the pins I think even if it did come loose it would stay in place until the cover is lifted again.

 

[WREKS]

@jmargo Hopefully, that is how it will play out. I do wonder how it was dislodged? In 'Oh just pullin a 15 month old sbt engine' post #36 @Jaycav evidenced a shredded chain guide that probably led to engine failure. However, it was the chain guide on the intake side, not the one on top.

 

[tdonoughue]

I would remove the 4200. See 3M™ Marine Adhesive Sealant Fast Cure 4200: 06560 • 06564 • 05260 - Technical Data Sheet

4200 is only rated to 190 degrees. And when exposed gasoline (other petroleum?--it doesn't say) and 'harsh chemicals' it softens. I don't think you want a hunk of 4200 coming off and floating about in there...

 

[jmargo]

I would remove the 4200. See 3M™ Marine Adhesive Sealant Fast Cure 4200: 06560 • 06564 • 05260 - Technical Data Sheet

4200 is only rated to 190 degrees. And when exposed gasoline (other petroleum?--it doesn't say) and 'harsh chemicals' it softens. I don't think you want a hunk of 4200 coming off and floating about in there...

Guess the cover is coming back off.

 

[mrcleanr6]

Some rtv silicone will work for this

 

[tdonoughue]

Guess the cover is coming back off.

Sorry about that. But I would rather tell you now than to tell you later after an issue...

But, hey! Your JB Weld is still good.

 

[jmargo]

Sorry about that. But I would rather tell you now than to tell you later after an issue...

But, hey! Your JB Weld is still good.

It's all good. I just need to figure out how to get the 4200 off.

 

[Ronnie]

I noticed a loose chain guide on one of my engines last off season when I had to take the valve (head?) covers off to get what was left of a spark plug which failed. As I recall the guide snaps onto two posts molded into the bottom of the cover. One of the flanges on one of openings on the guide (the dark circles in part 25 in the attached screenshot) moved further from the post than usual. I simply pushed the flange or lip of the guide back into position before reinstalling the guide. It seemed secure and the engine has run fine since but this thread and now knowing the cost has got me to commit to replacing both guides when I replace all the coils (preventive maintenance) this off season.

 

[tdonoughue]

It's all good. I just need to figure out how to get the 4200 off.

Oil... <kidding--couldn't resist>

I would just take a scraper to it. If that doesn't get it or enough of it, you can always use Debond on it. If it gets 5200 it will get 4200 no problem.

 

[jmargo]

Oil... <kidding--couldn't resist>

I would just take a scraper to it. If that doesn't get it or enough of it, you can always use Debond on it. If it gets 5200 it will get 4200 no problem.

Good thing is I ran the motor after so it has been pre-soaking. I just read about debond. Looks like it won't mess with the jbweld so that's good.

 

[tdonoughue]

@zipper could probably tell us for sure (he drinks the stuff), but I would be very surprised if it affected JB...

 

[I_squared_r]

I used oil safe rtv silicone.. Kind of silicone that can be used on valve covers. It held after 1 year and 60 hours run time. I periodically check my timing chain because I have the year with chain issues. I wouldn't use jb weld.. If that fails then you will have hard epoxy floating in your motor.