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| | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | As an interim engine , while I finish rebuilding the new one , I fitted a '54 235 to my '40. It's great , pulls much stronger than the original 216 , I'm kinda thinking I might keep it .
BUT .
It has a nasty , high frequency vibration , worst thru 1200 to 1800 rpm . Right where I normally drive . Really tingly thru the gear shifter .
Engine runs dead smooth and quiet at idle , not too bad at 2500 rpm (on the road) . I've been fantasizing that an engine builder just bored one cyl .............. LOL .
I fitted a new clutch assy at the time , had the flywheel and pressure plate balanced .
Now I'm wondering if the harmonic balancer is bad .
Has anyone had a similar experience . What was your fix . Thanks ,
Last edited by Dusty; 07/10/2019 10:39 PM.
| | | | | Joined: Dec 2003 Posts: 1,061 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 1,061 | If you have a running 235, I would not bother rebuilding the 216. My first thought would be a rod or main bearing that has too much clearance. Only a long shot guess. Did you run the engine before you installed the transmission? Another guess would be something in the trans. How is the compression? I am now out of hallucinations, anyone else?
1946 1-ton Panel
1952 1-ton Comml. W/Grain Body
| | | | | Joined: Mar 2004 Posts: 6,212 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,212 | Are you sure it's coming from the engine...could it be a bad U-joint? Mike B  | | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | First up , the truck was running perfect , smooth , just how you would expect a nice 78 year old 216 to run . I decided to change it due to the cracked block.
The 235 was a free engine , no history , sat on the garage floor for a long while . Compressions are 150 +_ 5psi . I started it on the floor . Sounded as good as you can guess with no exhaust pipe .
I swapped out the sm420 , for the original 4spd as I had fitted new bearing to the original box some years ago . It is a good g/box.
The vibrations are totally evident when just revving the engine at standstill .
No noise from bearings , no piston slap , a little valve lifter from 2 , just shakes .... (new engine mounts)
Still pondering dud harmonic balancer . | | | | | Joined: Feb 2004 Posts: 29,742 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,742 | Set the idle screw to the RPM where the shake is most evident, then start disconnecting spark plug wires one at a time to make sure all the cylinders are firing. A tachometer and a vacuum gauge will help isolate a cylinder miss- - - - -little or no drop in RPM and/or vacuum means you've got a weak cylinder. You can also run the engine for short time with the fan bet removed to rule out an unbalanced fan, or problems with the water pump or generator.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2011 Posts: 1,362 'Bolter | | 'Bolter Joined: Feb 2011 Posts: 1,362 | I think the key thing here is you had the flywheel and pressure plate balanced. Why? And it maybe the problem.
Kicking self for selling off my Taskforce trucks.
Still looking for an LCF or conventional big bolt in decent shape.
As of 10-26-2022, A 55.2 Taskforce long bed now the work begins
| | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | Trucko , I had the balance job done to try to eliminate this issue. | | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | Jerry , I will give your suggestions some work this weekend . Thanks . | | |
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