CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Crate motor, blue smoke?

broncoman6524

1/2 ton status
Joined
Oct 31, 2005
Posts
2,469
Reaction score
2
Location
chuluota Fl
ok put the gm 290hp crate longblock in my truck. edelbrock performer, 1406 carb, stock dizzy, new plugs wires etc everything was BRAND new. broke it in properly (baby it) for 500-600mi. now there is roughly 2800miles on the motor and the right bank is smoking.

i recently replaced the modulater in tranny (th400) AFTER motor swap bc it was smoking blue and the tranny shiftedlike a puss. i also swapped the vacuum hose and cleaned the little nipple thingy. now about 1 week later its STILL smoking but only at idle.

im thinking valve seals. its not clear enough err dark and enough blue smoke to be rings. atleast i hope not...lol. its prob due for an oil change too....its got 15s40 in it now. ya i know 10w30 is waaht it calls for. but after the breakin oil this is what mea nd my dad felt was best...
 
Last edited:
broncoman6524 said:
ok put the gm 290hp crate longblock in my truck. edelbrock performer, 1406 carb, stock dizzy, new plugs wires etc everything was BRAND new. broke it in properly (baby it) for 500-600mi. now there is roughly 2800miles on the motor and the right bank is smoking.

i recently replaced the modulater in tranny (th400) AFTER motor swap bc it was smoking blue and the tranny shiftedlike a puss. i also swapped the vacuum hose and cleaned the little nipple thingy. now about 1 week later its STILL smoking but only at idle.

im thinking valve seals. its not clear enough err dark and enough blue smoke to be rings. atleast i hope not...lol. its prob due for an oil change too....its got 15s40 in it now. ya i know 10w30 is waaht it calls for. but after the breakin oil this is what mea nd my dad felt was best...
how many miles do you have on it?i have the same engine and i changed the oil 10 times as i was getting it going.mine was broke in with a bad carb.10/30 is what you need to keep in it.
 
Aftermarket Valve covers??..

If you are not using stock valve covers,many of the aftermarket ones lack baffles for the PCV valve,and allows oil to be sucked in and burned..also,many have no "breather" hole on the passenger side cover..without a breather,the PCV valve will suck air past the rings,valve giudes,dipstick tube,etc..that can cause smoking and escessive oil consumption too..

Some motors take quite a long time to "break in"..I've seen "Mr. Goodwrench" motors smoke for 15-20,000 miles,and just before the owners got disgusted enough to complain to the dealer they got them from,they finally started to stop smoking,and get better gas mileage..some motors with chrome rings never seem to "break in",and guzzle oil from day one..:crazy:
 
i dont think its pcv. its got true duals and if it were the pcv it would smoke on the both sides...it smokes on the pass side.


could it be that tehre could be tranny fluid stll in the intake. runner? bc its on hte pass side adn when i replaced the modulator it smoked a little bit less.
 
How did you get tranny fluid in the intake?(the intake is not the dipstick for the tranny..lol) if theres alot you might as well pour water down the intake....:doah: j/k using the wrong type of oil for a motor (especially synthetic brands) on a new motor ruin the seal between the rings and the cylinder walls. This may cause scoring on the cylinder walls aswell. Go to a mineral based oil for a while, if you arent already. Ive seen this on countless motors. Also does your motor have vacuum at the pcv valve? if you have a plugged drain back hole in your head, this might cause the symptom youve been having aswell..
 
What oil does the info with the engine say to use? What makes you think you know better than GM as to what oil to use? I'm not saying this is your issue, just wondering where the mind of "well I just bought an engine that these guys built, I know better what oil to run", came from.
 
weird, weird, weird,
I have the same motor (290 horse SBC) bought new (1 year ago), and i have one side that smokes as well. I did however have an overheat problem with mine early in its life, which i've always blamed on my smoke problem.
My motor has aprroximately 4,000 miles on it, it runs flawless, it just smokes out of one side. So i've just decided not to worry about it.

I also run a 1406 carb on a performer mani, headers, and an hei dist.

BTW.....i figure out how to solve the problem...... I picked up an 8-71 blower so i'm gonna soon tear it out and re-do the motor anyway.
 
Not to be off topic but was that hit at me "sled_dog"...If it was im sure if you talk to engine builders that will tell you that if you start with synthetic fluid then you run risk of ruining your motor.. By the way as a technician i see many of the most moronic stuff the automakers come up with.... But hopefully this wasnt against me....
 
RIPPEDK5 said:
Not to be off topic but was that hit at me "sled_dog"...If it was im sure if you talk to engine builders that will tell you that if you start with synthetic fluid then you run risk of ruining your motor.. By the way as a technician i see many of the most moronic stuff the automakers come up with.... But hopefully this wasnt against me....

wasn't towards you man. Was to the original poster. I didn't even read your post to tell you the truth. I know what you mean about not running synthetic through an engine being broken in. I am a dealership tech as well... in a Ford shop, believe me I see my share of moronic moves on the part of manufacturers. But 10w-30 is just what standard old small blocks run, don't see any reason to go anywhere else, unless the engine is worn out.
 
No harm done. I had just had my 355 recently built and my engine builder said not to use synthetic at the start of a motors life, thats all..you can use what you want...my motor never smoked... Does your motor have a good set of rings in it?
 
RIPPEDK5 said:
How did you get tranny fluid in the intake?(the intake is not the dipstick for the tranny..lol)..

As someone mentioned, a bad vac modulator can allow atf up into the intake...

Best bet at this point would be a leak-down test and/or a little visual with a boroscope...
 
idk why i ran 15w40 kinda retarted on my part...like ryoken said as a modulator will got bad the intake vaccuum will suck some fluid into the intake...

i believe its got a set of good rings. if you mean like sound ones...the motor runs like a champ adn ive got no problems it just smokes to the one side...idk F*ck it. guess ill just live with it. its under warranty still :) LOl
 
Top Bottom