Ironhead Primary cover is damn HOT

Ferg · #1 22nd August 2009

My new to me '76 XLCH has done great on <1 hour rides. I took it on a 4 hour jaunt yesterday to really test everything out since I have changed the engine oil, primary oil (all H-D product), plugs, and all the other normal tune-up activities. When I get back home I notice that the black decal on the primary cover has come off and the primary cover is freakin' HOT. Pretty much just as hot as the engine case. I check the cover on the other side and it's also very hot. Oil temp from my dipstick gauge never toped 195.

Is this normal given the unit construction and the proximity to the case? I saw that a few drops of oil came out of the inspection cap during the ride but no other leaks.

Ferg

Schutzhund · #2 22nd August 2009

Generally the engine gets a little hot. When you say friggen hot what do you mean, as in it will cause burns when touch it?

IronMick · #3 22nd August 2009

The decal on my p cover started to come off one time as some gasoline had spilled on it and disolved the adhesive. I have never really noticed how hot the p and cam covers get normally.

Ferg · #4 22nd August 2009

Using my very scientific method of sticking my hand on various parts of the bike, the primary cover was almost as hot as the heads. Could only touch for a couple seconds max.

On a R75/5 BMW I have, the final drive case once got burning hot because too much pressure was building inside due to the fact that it was sealed too well. Could the same be true to the primary cover? Isn't the filler cap vented??

bustert · #5 22nd August 2009

i agree with mick. 195 is just shy from boiling water (212) and you couldn't put your hand on it long. my cases get hot also. i lost my decal 25 yrs ago, the factory glue held on for a long time but the taiwan knock off labels probably have lack luster adhesive and just cut loose from heat. if you think about it, that is how you take formica off a counter top. try to find a more suitable adhesive.

SilverShark96 · #6 22nd August 2009

Quote:

Originally Posted by Ferg

Using my very scientific method of sticking my hand on various parts of the bike, the primary cover was almost as hot as the heads. Could only touch for a couple seconds max.

Wow! You just have a hell of a pain tolerance, because there's no way I'd even attempt to touch my heads at full operating temperature! That's not hot, that's scalding.

1976 XL · #7 22nd August 2009

The oil from the points cover is an oil seal leak. If it isn't a lot it will work for a while, but I would get a new seal soon in case it gets worse. If it gets too bad the ign. system will ground out. That means roadside servicing.

Ferg · #8 22nd August 2009

Found my IR temp sensor...

After a 25 minute ride here is roughly what I remember:
Top of heads (by bolts): 195 degrees
Middle of heads (inside cooling fins): 290
Top of engine case (by VIN #): 250
Primary cover: 90 (it was MUCH cooler than when I wrote this original email after my 4 hour ride)
Points cover (rear):120
Points cover (front by generator): 195
Outside of oil can: 120 (oil temp was 155 inside)
Exhaust by port: 300+

Okay so the ride was not that long and I need to take some more measurements but I'm curious how this compares.

I'm going to create a sheet and take some measurements the next week or so when I get back from rides to see how these change.

Safe ridin'... Ferg

Schutzhund · #9 22nd August 2009

This sounds interesting. What type of thermometer are you using to take these temps? Let us know and maybe several people could take temps, and come up with an average.

SilverShark96 · #10 23rd August 2009

Quote:

Originally Posted by Schutzhund

This sounds interesting. What type of thermometer are you using to take these temps? Let us know and maybe several people could take temps, and come up with an average.

It sounds like he was using one of those Infrared point-and-read temperature guns. Am I correct? As far as I know, they are pretty accurate.