Rod knock?
#1
Junior Member
SHOW GUEST
Thread Starter
Join Date: Mar 2008
Location: Central Minnesota
Posts: 7
Rod knock?
:evil: Maybe this post should be in the angry venting category...???
So I was helping troubleshoot a SBC problem over the phone Sunday evening. Sure sounded like a rod knocking - but it was over the phone... I wanted them to check the valves but they were going to pull the engine instead.
Today the knock was quieter and then went away after revving the engine a little bit???
Now I hear it's running fine and that they did check the valves - one lifter was stuck up??? I call BS! The engine would be backfiring one way or another if the valve was open. How can a lifter get stuck upward after doing a carburetor swap?
Anyone hear of knocking "going away" the next day?
So I was helping troubleshoot a SBC problem over the phone Sunday evening. Sure sounded like a rod knocking - but it was over the phone... I wanted them to check the valves but they were going to pull the engine instead.
Today the knock was quieter and then went away after revving the engine a little bit???
Now I hear it's running fine and that they did check the valves - one lifter was stuck up??? I call BS! The engine would be backfiring one way or another if the valve was open. How can a lifter get stuck upward after doing a carburetor swap?
Anyone hear of knocking "going away" the next day?
#7
Junior Member
SHOW GUEST
Thread Starter
Join Date: Mar 2008
Location: Central Minnesota
Posts: 7
It's a stock 350, cast pistons, hydraulic lifters. It does have a mechanical fuel pump... Never heard one stick before.
Over the phone this thing was thumping pretty hard. They said the sound seemed to come from down in the center of the engine.
Who knows??? :?
Over the phone this thing was thumping pretty hard. They said the sound seemed to come from down in the center of the engine.
Who knows??? :?
#8
Senior Member
RACING JUNKIE
Join Date: Sep 2007
Location: orland pk il
Posts: 2,399
mechanical fuel pump. i had a new pump arm stick and not return fast enough and knock against the cam and sounds like a rod knock that can come and go. push rod for pump could be binding in its bore and do the same.
#10
I have heard a terrible knock in a chevy 350 in a corvette..it was carbon on top of piston , sounded just like a rod...poured trans fluid in carb with engine revved up to break it loose , knock went away , still running today..