73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Performance => Topic started by: popsthebuilder on October 03, 2013, 09:08:12 pm
-
73 c20 350 350
It has been a while since I posted. My truck has been running pretty bad lately. Complete lack of power coupled with an abundance of unburned gas coming through the exhaust. I changed out a plug thinking that would help some. It worked for about half an hour. Oil is getting into the combustion chamber of multiple pistons, and one is getting a large hard blackish deposit, I'm not ready to rebuild the motor yet. What can I do temporarily to get her to run better? going to attempt switching to hei tomorrow. Is there anything special I need to know to switch from the oe distributor? What is the easiest way to convert the 12v wire that goes to my coil now to one with a clip or something that can slide around the electrical connector on the hei? Thanks.
-
If you have a resistance wire for the points distributor, you will need to run a new wire (12-14 gauge) from a 12v source that has power when in the "on" and "start position. This will power the HEI "BAT" terminal. You will also need some new plug wires unless your wires now have female terminals at the cap. You can find the "clip" style connector at an auto parts store.
You may have some leaking valve stem seals and oil is entering the chambers and causing the oily residue on the plugs. You can change the seals without pulling the heads with a few special tools.
-
Go hei and use delco 45 plugs. That's what I use and the plugs are hotter so they don't let the oil build up on them. Also make sure the plug wire connectors snap on at the plugs. They trend to heat up and loosen.
What's under the hood??? If you have to ask maybe we shouldn't race...
-
HEI dist. came with vacuum advance stop. What should I set this to? Do I even need it?
-
If possible use it to limit the vac advance can to only pull 8 to 10 degrees. That with 32 to 36 degrees mechanical timing will make your engine perform it's best.
What's under the hood??? If you have to ask maybe we shouldn't race...
-
Set vac. advance stop between 8*-11*. She started, ran better briefly then died. Couldn't find timing mark on balance. Drove down the road. She was running, and a whole hellofa lot better, but still seamed to maybe be missing on one cylinder still. Hit a little ruff terrain, nothing crazy though. Got back to find the truck pouring water from the water pump to engine area. Alternator belt has also spun showing the grooves over the pulley. How could that have blown out the water pump gasket? I'm somewhat confused. Any help/ advice? Anyone?
-
Swapped out water pump, and belt earlier. Ran fine, no leaks. I got on it and it blew out the gasket again. Also blowing a blue smoke at full throttle. Now I'm screwed. No more gaskets. Could there be a crack in the block? What should I check first?
-
If your blowing water pump gaskets there's a clog somewhere. In the t stat installed?
What's under the hood??? If you have to ask maybe we shouldn't race...
-
That crossed my mind. A few months ago I changed water pump, radiator, and when I tried to change out the thermostat I broke off the stud holding the alternator bracket. Guess a solution to that problem is over due. Thanks for the help.
-
If your blowing water pump gaskets there's a clog somewhere.
As 454 said, I would start with the bolt you broke and check that thermostat, most likely you will need and new one.
-
fix that stud but nothing with the thermostat would cause it to blow out a gasket. to my knowledge (could be very wrong) the water pump pulls from the bottom hose and circulates the water threw the engine to the heater core from there it returns back to the rad. whatever doesn't circulate gets pushed threw the bypass hole under the main hole on the water pump. this is how the water flows (before) the thermostat opens up. now back to the gasket, four things i can think of....
1 water pump bolts are too long and your not getting the proper tq on them
2 mounting surfaces not flush
3 too much rtv
4 maybe just maybe a blown head gasket
also with the engine cool pop the rad cap and start it up, are there a lot of bubbles. any loss of coolant?