M62tub - Mystery Dowel Pins & Hylomar on the lower timing cover gaskets

[ddavies]

Hello all, New to forum posting but long time forum lurker. I am currently changing the timing chain guides, and all the other "fun" m62 stuff, on my 2000 540iT and found two mystery dowel pins buried in some grease. It's the first time the engine has come apart during my ownership so it would have been from some previous engine work. They were buried in a fair amount of grease so I would suspect they've been there a while.

The dowel pins were found in the valley of the block and on the top side of the lower timing chain cover.
IMG_3776.jpgIMG_3775.jpg


The pins measured out to 11.68mm x 4.49mm
IMG_3845.jpgIMG_3846 2.jpg

Lastly, I have a question on sealing the Lower timing cover.

Ive seen a number of people saying that they do not put any additional sealant on the three metal lower timing cover gaskets, with additional sealant only being applied to the upper oil pan gasket and receiving surface as well as the joint where the heads/block/lower & upper timing covers meet.

This goes against the Bentley Manual that suggests "Apply a thin coat 0f Three Bond 1209 to the front and back of new seal."

I had planned to apply a thin coat of Hylomar Blue to the upper oil pan gasket, the three metal gaskets for the lower timing chain cover and all receiving surfaces. Would anyone suggest NOT using Hylomar on the three Lower timing cover metal gaskets?


Thanks for any help that can be provided!

Dane

[CPHES]

Good luck - can a mod move this to the main e39 thread?

[ddavies]

Thanks - Yeah, I was kicking myself for not posting it in the main e39 thread - hopefully a mod can move it!

[JimLev]

Moved it for ya.
Those dowel pins look to small for this engine.
There are 2 pins on the bottom sides of the lower timing cover but they are larger.
The heads have pins too, but larger than the ones you have.

I used hylomar, but not on the metal gaskets on the distribution units.

[RosieE39]

They’re bearing rollers.
Probably from the water pump.

[scubajim20]

I used the permatex gasket dressing on all the timing cover surfaces and the VCG surfaces. It was a very thin skim coat at best. Just about a year now and no leaks to report.

[ddavies]

Moved it for ya.
Those dowel pins look to small for this engine.
There are 2 pins on the bottom sides of the lower timing cover but they are larger.
The heads have pins too, but larger than the ones you have.

I used hylomar, but not on the metal gaskets on the distribution units.

Thanks for the move!

Yeah the pins are quite small - after looking through REALOEM I couldn't find anything close to that small, but wanted to make sure I wasn't missing anything.

Good to know on the Hylomar, I think it will be going on everything expect the Vanos distributuon units

They’re bearing rollers.
Probably from the water pump.

Was thinking the the same thing for a minute, but thought that would be quite a burly bearing with rollers that big. I have an old water pump now, I could tear into it some day to find out.

I used the permatex gasket dressing on all the timing cover surfaces and the VCG surfaces. It was a very thin skim coat at best. Just about a year now and no leaks to report.

Great to hear! That's the plan for mine too


Thanks for all the info