'82 Johnson 70hp, I need a part # (with pics)

[laurentide]

Hi, I sucked up some weed the other night and had an overheat situation. I just rebuilt the water pump, replaced t-stat and gasket, and checked compression which is good and consistent. I do have a head gasket just in case. It's running fine now, but....the main problem was that the heat blew out at least one of the exhaust manifold gaskets which was leaking water when started back up. I just pulled the three plates off and I'm trying to get a part #.

In this pic, it goes gaskets/plates from what would be the powerhead on the far right. So far I have 0331917, 0331916, again from right to left. The gasket on the far left (to the right of the cover plate) I can't seem to find. Any assistance would be greatly appreciated.

This one in the middle between the two plates is what I need:

Another question, which sealant should I use with these? Or any at all if they're "new" style gaskets?

Thanks very much! I've been meaning to replace these so this failure was a good motivator!

 

[Vic.S]

I find 0319097 but I dont agree with the numbers you quote for the other two gaskets. They are for '86, '87 and '88 models

Check with the BRP parts list at http://epc.brp.com/Index.aspx?lang=E&s1=965ea739-91b2-465d-806d-9ddbac71ce6d

 

[laurentide]

OK, thanks, I'll do that.

EDIT: Yeah, no luck online for that part so far, and the replacement part doesn't look right. Those other part #s are both replacements, too, but they look right. I'll try my local dealer tomorrow. Cheers.

 

[Watermann]

Hey Chem it would help to have the model and serial for the motor but here is the schematic (came out small) I found at marineengine dot com. They show the 3 gaskets in stock, 28, 30 & 86.

 

[laurentide]

Watermann, it's j70elcnb, and I've looked at 86 about 20 times but I think it's the same as 30 based on the pics. I think I'm going to cut my own. Thanks.

 

[laurentide]

Update on this darn exhaust manifold project: I now realize that I should have performed this very simple test before reinstalling the baffles. I didn't, and I got water in the lower cylinder again. So, back to square one. I believe that I already know the answer to this (I need a new inner plate), but figured I'd just check here.

My block is arrow straight in all dimensions, both on the exhaust side and the cylinder head. However, the inner plate shows some warping...but I want to make sure that I'm beyond the tolerance range. Some pics:

Mostly cleaned inner plate:

Straight edge:

Yep, that's daylight:

.025/.635 feeler gauge fits in the gap:

So, that's bad, yeah?

I did find this for $100 on ebay, which seems like a fair price for a newly manufactured piece (less than half of the NLA OEM part):

Just grab the new aftermarket one?

Many thanks!

 

[laurentide]

Another question that just came up...I just put a new head gasket on and ran a compression test. I fogged the heck out of the crankshaft with MMO after getting water in there, so there was still a bit of oil running out of the lower cylinder. Would that give me a high comp reading? It was like 160 compared to 130/135 for the other two. Cheers!

 

[Bosunsmate]

yes it could.
Have you tried shaving the exhaust plate down a touch on a flat sheet of glass with fine sandpaper?
It might just take those high ends down enough to work without the need to spend $100 on a replacen\ment

 

[laurentide]

yes it could.
Have you tried shaving the exhaust plate down a touch on a flat sheet of glass with fine sandpaper?
It might just take those high ends down enough to work without the need to spend $100 on a replacen\ment

Well, I already ordered it....but, the other plates are not quite true either, just not as bad. So I'm going to try this method on those while I wait for the part to arrive. That's helpful, as I didn't realize that was possible with these. I'd feel better about reassembling with straight plates. Thanks for the reply!

PS: That gasket that I was looking for in the OP must have been put in by a previous owner, 'cause I really don't think it's the right one...the passages don't line up with anything. So I finally took the good advice that was offered above and ordered the supercession chain ones.

Compression evened out on another test, too. 130, 135, 140 top to bottom, and nice blue spark.