OzVMX Forum

Clubroom => Tech Talk => Topic started by: Bitten on July 04, 2011, 02:36:09 pm

Title: Engine / crankcase operating temp
Post by: Bitten on July 04, 2011, 02:36:09 pm
Another question for the beginner, please forgive!

What operating temp does the average crankcase operate at?

I stuffed up the paint job and need to redo, I have resigned myself that to do it properly again I will need to re-strip the transmission again but I don't want to remove the seals and bearing again in case I damage them

The paint I am using calls for a 250 deg C for 1.5 hours to cure, will this temp exceed the bearing and seals heat tolerance?

Cheers

Bitten

Title: Re: Engine / crankcase operating temp
Post by: Mike52 on July 04, 2011, 02:53:50 pm
The paint I used said 200c for 30 mins.
Smoked the house out ,turned grey and  washes off in petrol.
Guys on this forum say 80c will do the job.
http://ozvmx.com/community/index.php?topic=17756.msg177899#msg177899
Title: Re: Engine / crankcase operating temp
Post by: PEZBerq on July 06, 2011, 11:09:11 pm
There is no way a crankcase operates at 250 deg C. The oil wouldn't survive and it would be radiating heat like an electric heater! Husky cranks are heated to 200 deg C to get the crank bearing to loosen and drop out!
Title: Re: Engine / crankcase operating temp
Post by: Bitten on July 07, 2011, 09:35:23 am
Thanks guys

I have decided to carefully removing all the bearings and seals and do it properly

I had a crack at curing the magnesium clutch and magneto covers on the BBQ at 100 deg (ish) for 1.5 hours and they seemed to have cured really well so the 250 deg the paint states may be what the woodstove operates at once you fire it up after painting and not what is necessary to cure the actual paint

Anyway thanks

Bitten
Title: Re: Engine / crankcase operating temp
Post by: AdamN on July 07, 2011, 12:04:51 pm
Hey Bitten, have you got the Plasti-Kote paint yet? How'd it go?

Adam
Title: Re: Engine / crankcase operating temp
Post by: gettinold on July 07, 2011, 01:13:49 pm
good to see the barby coming in handy.
Title: Re: Engine / crankcase operating temp
Post by: Bitten on July 07, 2011, 01:35:11 pm
Hi Adam

I posted this on the other thread but ......

"After searching for Plasti-Kote Woodstove as recommended by Adam and told it is no longer being brought into Australia I discovered it is made by a company called Valspar who are the parent company of Wattyl paints. I do a lot of work for the very good people at Wattyl and I was in a marketing meeting yesterday and casually asked the question about Plasti-Kote Woodstove and was told that yes it was deleted BUT they are about to launch a new range of Killrust heat resistant paints in August and whilst they could not put their hand on their hearts and say it was the same formula they threw me a can of the new Killrust Woodstove to try!!"

The brake plates, crank cases and covers have all come up fantastic. I etch primed them, 2 light coats and one a bit more heavier and cured for 1 hour and I am really happy with the finish, a real soft satin black and they look to be a lot more durable than the VHT, thanks for the advice and when Killrust Woodstove is released in August I can highly recommend it

Cheers

Bitten
Title: Re: Engine / crankcase operating temp
Post by: AdamN on July 07, 2011, 02:10:13 pm
Better stock up when I see it on the shelves then :o. I didn't know it was deleted >:(
Although it does sound like the new stuff if pretty much the same colour by the way you describe it

Adam