I have a 250 straight 6 with chrome side covers and valve cover from Speedway. They ****, and with fresh gaskets and high temp silicone they still leak. I know its going to leak a bit but I shouldnt have the mess I have today. Anyone got any tricks for these flimsy covers that dont torque down even?
silicone always leaks in my experience. make damn sure the surfaces are as clean, dry and straight as humanly possible. make sure you are using the best gasket you can get. try some gaskacinch, indian head or aircraft sealer. put the pieces in place according to the directions and let everything set up before step torquing everything gently and evenly. then re torque after a couple of heat cycles.
That cheap Taiwan flimsy **** will ALWAYS leak. You cannot get ANY compressability on the gaskets. Take stock G.M. covers and have them chromed or powdercoated. Oh yea and the chrome thermostat housings from Taiwan,you can ****can them too!
if there is any oil on the surfaces to be sealed oil will weep right thru the area still oily cleaned flat chrome covers will seal scuff surface areas if ya must to get the sealant to stick resist over tightening it warps the cover and lets oil out did ya put on the right oil cap ya need a breather type ya know presuure/ blow by / over filled oil ..??????? i always had good luck with the high tack and seal.. . follow directions glue gasket to cover first ....
I do not have a breather type oil cap....... Maybe I will start with that and see if it helps. Thanks!
First off silicone and gaskets should not be used together! One or the other! U can used high temp silicone as a gasket. If you use both its like having 2 totally dif gaskets.
Using chrome load spreaders under the bolts is a big step in the right direction with cheapo chrome tinwork. Good luck
Got the load spreaders and it is a gasket sealer that I used with cork gaskets. Im pulling it apart, scuffing the chrome, replacing the gaskets and using a breather cap. That should be a step in the right direction. Any tips on the side covers? Thanks for helping a rookie!
Do the same thing for the side covers. Make sure you have clean, dry surfaces, rough up the chrome for a little bite and use rubber cement to bond the gaskets to the valve covers and side covers before you install them. Torque as evenly as possible using spreaders. If they still leak hang the chrome **** on the wall and use OEM covers that are not warped. -Bigchief.
...there's a new sealer out call'd the Right Stuff, probly available at NAPA, etc. You don't need gaskets, just use the sealer. Some of my friends say it really works great.
See if you can find rubber gaskets for these parts. We always had issues with our circle track cars puking oil out the valve covers when we used cork gaskets, switched to rubber, torqued to spec, no more black flags. Fel-Pro kits with rubber gasket usually have a -R at the end. Good Luck!
Even on the cheap ****...it helps to sand or grind the chrome plating on the gasket surface for the sealer to have some "tooth" to stick to it. Shiny chrome doesn't seal well.
If you can't get the tin to seal, several companies sell aluminum covers for both locations on the 250. +1 for Right Stuff, evil, nasty looking **** as you put it on, but doesn't seem to leak.
Mercury (as in outboard motors) make a really good gasket sealer. They also make nice rocker and side covers for the Chev 250. They show up on ebay occasionally.
Trade it for a 283? Uh, never ever buy Speedy Bill's junk? Oh you mean you want to fix what you already have with what you already got right? You can put Corvair hold downs on the rocker cover that'll help. As for the silicone the trick is make damned sure that the area is really clean; MEK comes to mind. Then don't over so it just a thin coat and wait until it is good and dry before you light it off; like in overnight.
The Jalopy Journal
