400 is in but with a problem
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
400 is in but with a problem
The 400 is in but it has a problem that I’m hopping you guy’s will tell me it’s no big deal to fix.
I fired it up for the first time and she made was making a lot of noise. I started looking for the problem and the saw sparks flying from under the harmonic balancer which is hitting on the cross frame thus the noise.
Please tell me I can remove it without having to take the engine out again and once it is out I can put on the one from the L98.
I didn’t notice before putting the motor in that the balancer is bigger then the L98’s.
I fired it up for the first time and she made was making a lot of noise. I started looking for the problem and the saw sparks flying from under the harmonic balancer which is hitting on the cross frame thus the noise.
Please tell me I can remove it without having to take the engine out again and once it is out I can put on the one from the L98.
I didn’t notice before putting the motor in that the balancer is bigger then the L98’s.
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
If the motor is running, your clearance problem is probably not major. Remove the through bolts on the motor mounts, use a die grinder on the crossmember where there is contact and check before starting up. If you have a quarter or an inch or so of clearance, you might be good to go.
Melting Slicks
Joined: May 2010
Posts: 2,082
Likes: 3
From: Conowingo Maryland
If the motor is running, your clearance problem is probably not major. Remove the through bolts on the motor mounts, use a die grinder on the crossmember where there is contact and check before starting up. If you have a quarter or an inch or so of clearance, you might be good to go.
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
The motor is running but it’s making a loud banging noise, I assume it is from hitting the frame.
I had a 350 in a boat that made a similar noise that no one could figure out even a local engine builder and they removed the pan. Turned out the boat had water in the bilage through the winter and when it froze it pushed the pan up into the crank so every rotation it made a bang. Damn I had to figure that one out myself.
I’m hopping this noise is from hitting the frame if not I have a whole new problem.
I think I would prefer to remove it and put the L98’s balancer on it but will it work and
how do you remove the it?
I had a 350 in a boat that made a similar noise that no one could figure out even a local engine builder and they removed the pan. Turned out the boat had water in the bilage through the winter and when it froze it pushed the pan up into the crank so every rotation it made a bang. Damn I had to figure that one out myself.
I’m hopping this noise is from hitting the frame if not I have a whole new problem.
I think I would prefer to remove it and put the L98’s balancer on it but will it work and
how do you remove the it?
Pro
Joined: May 2002
Posts: 635
Likes: 6
From: New Jersey
I put a 400 in a freind vette in had the same problem, the 400 balancer is a little larger than the 350s, Just get a smaller balancer, but you need to know whether your engine was internal or externally balanced.
Randy
Randy
Last edited by rlane5; May 14, 2011 at 10:50 AM.
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Drifting
Joined: Oct 2006
Posts: 1,328
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From: Stafford Connecticut
I have a 400 small block in my 88.You need to use a 6 and 3/4 inch externally balanced damper.You can not use your l98 balancer it is internally balanced.Your motor will have a really bad vibration if you use the stock L98 balancer.I got my 400 balancer from CNC motorsports for $59,works great.This is assuming you are have a stock 400 rotating assembly.
Last edited by steven mack; May 13, 2011 at 07:45 PM.
Thread Starter
Pro
Joined: Nov 2009
Posts: 583
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From: Maple Grove Minnesota
I have a 400 small block in my 88.You need to use a 6 and 3/4 inch externally balanced damper.You can not use your l98 balancer it is internally balanced.Your motor will have a really bad vibration if you use the stock L98 balancer.I got my 400 balancer from CNC motorsports for $59,works great.This is assuming you are have a stock 400 rotating assembly.
Thread Starter
Pro
Joined: Nov 2009
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From: Maple Grove Minnesota
Race Director
Joined: Apr 2003
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From: moraga ca
I'm trying to picture what you are saying and I'm having trouble. Are you saying put spacers between the motor mounts and the block? If so, that won't work since the mounts are bolted to the block at about a 45 degree angle and the through bolts won't line up. The flanges for the through bolts are part of the frame, so that can't be shimmed up. What am I missing?
Le Mans Master
Joined: Aug 2010
Posts: 9,272
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I was thinking LS style , my bad, it could still work with a 1/4" plate on each side and longer bolts, would just be more thinking and if the dampener is only rubbing should provide enough clearance. possibly elongate the holes in the spacers.
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
NOW ya tell me...after we have done it several times, sbc1 and bbc engines...also seen 1/2'' nuts used as spacers only on the two top mount-to-block bolts with no spacer on bottom bolt, some one should tell them too.
Last edited by redrose; May 13, 2011 at 08:49 PM.
Le Mans Master
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Le Mans Master
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
I have a 400 small block in my 88.You need to use a 6 and 3/4 inch externally balanced damper.You can not use your l98 balancer it is internally balanced.Your motor will have a really bad vibration if you use the stock L98 balancer.I got my 400 balancer from CNC motorsports for $59,works great.This is assuming you are have a stock 400 rotating assembly.
