help troubleshoot rebuilt engine
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
help troubleshoot rebuilt engine
I went to break the cam today in accordance with:
http://www.crateenginedepot.com/suinst.html
but we did not get to do it.
The first problem...I forgot to torque down the valve covers and when I brought the engine up to 2000 rpm, oil started leaking out like a seive.
Okay, fixed that problem. Next problem, I ran out of gas. I am running gas out of 2 1/2 gallon gas cans. I went through 2 1/2 gallons in 15-20 minutes.
When I started the engine, white smoke came out of the driver side exhaust pipe for a couple of minutes, then out of the passenger side for a couple of minutes.(alternating). When the engine reached operating temp (it was 50 degrees outside) there was a little presence of white smoke...more like visible exhaust, not so much smoke.
White smoke is for water right? The engine is completely rebuilt and was test fired 6 weeks ago. The exhaust is new, the coolant system is new, the cam, pistons, valve train are all new. Everything is new or re done.
Is the start up smoke anything to be concerned about, the oil is still "new looking,"? Is the excessive fuel consumption due to timing? Thanks.
btw 69 350/300 (with mild cam), 3 spd man, rochester carb
http://www.crateenginedepot.com/suinst.html
but we did not get to do it.
The first problem...I forgot to torque down the valve covers and when I brought the engine up to 2000 rpm, oil started leaking out like a seive.
Okay, fixed that problem. Next problem, I ran out of gas. I am running gas out of 2 1/2 gallon gas cans. I went through 2 1/2 gallons in 15-20 minutes.
When I started the engine, white smoke came out of the driver side exhaust pipe for a couple of minutes, then out of the passenger side for a couple of minutes.(alternating). When the engine reached operating temp (it was 50 degrees outside) there was a little presence of white smoke...more like visible exhaust, not so much smoke.
White smoke is for water right? The engine is completely rebuilt and was test fired 6 weeks ago. The exhaust is new, the coolant system is new, the cam, pistons, valve train are all new. Everything is new or re done.
Is the start up smoke anything to be concerned about, the oil is still "new looking,"? Is the excessive fuel consumption due to timing? Thanks.
btw 69 350/300 (with mild cam), 3 spd man, rochester carb
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
The oil looks fine, the carb was just redone and is fine. I've talked to some friends and we agree that the timing is just off. I am going to get a five gallon can gas and go through the cam break in procedure, and then set the timing. I'll let you know as I get it dialed in.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
Found the gas. The return line has been routing fuel back in to the gas tank. There is about four gallons of gas in the tank.
Should the fuel return line be bringing that much gas back into the tank?
Should the fuel return line be bringing that much gas back into the tank?
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
Rich
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
That could be normal. I've watched the fuel in the tank when the engine was running on my '69. It swirls around quite a bit from the force of the returning fuel. When you have a return line, the fuel pump is pumping on every stroke, and what the carb doesn't use goes back to the tank.
Thread Starter
Drifting
Joined: Sep 2002
Posts: 1,614
Likes: 7
From: South Florida
Okay. The cam is broken in.
The gas problem is not a problem. The fuel system works fine. The carb that Lars built works great. The timing (following Lars paper) was almost dead on to start with. I had to decrease the dwell 3-4 degrees and had to retard the timing 2 degrees. I may have to changes the springs in the distributor because I am not getting my full advance at 2500 rpm. The advance settles down at 2500 rpm but then jumps +4 degrees between 3000 rpm and 3500 rpm.
I still have some white smoke out of the exhaust pipes, but it could be a combination of condensation (the pipes aren't tightened up yet) and burning resdidual packing grease off of the new parts.
The engine sounds and runs great. Now all I have to do is set the rings when the body is back on and I can drive it.
The gas problem is not a problem. The fuel system works fine. The carb that Lars built works great. The timing (following Lars paper) was almost dead on to start with. I had to decrease the dwell 3-4 degrees and had to retard the timing 2 degrees. I may have to changes the springs in the distributor because I am not getting my full advance at 2500 rpm. The advance settles down at 2500 rpm but then jumps +4 degrees between 3000 rpm and 3500 rpm.
I still have some white smoke out of the exhaust pipes, but it could be a combination of condensation (the pipes aren't tightened up yet) and burning resdidual packing grease off of the new parts.
The engine sounds and runs great. Now all I have to do is set the rings when the body is back on and I can drive it.
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Instructor
Joined: Nov 2007
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From: Sugarland Texas
Oil
Condensation in your pipes comes out of the exhaust like steam, then fades away. White smoke is burning oil, on a new engine there could be a little, but not much if any at all. Keep a eye on the white smoke. Black smoke out the exhaust is you are running your carb to rich.