FH601V has whistling sound

sgkent

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general rule is that bearings need 10 PSI minimum per 1000 RPM.
 

bertsmobile1

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That is quite normal.
Cold oil is thick so holds pressure much better & longer than hot oil
Cold engines have smaller clearances than a hot one when the parts have expanded .
 

Hayward51

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That is quite normal.
Cold oil is thick so holds pressure much better & longer than hot oil
Cold engines have smaller clearances than a hot one when the parts have expanded .
I changed out oil pump and pressure relief spring/ball. Didn't help noise or oil pressure.
 

sgkent

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Is your stethoscope solid on the end like the one I have? If so, listen to the case in that area, then use a hose in the same area to see if the sound is louder or softer near the case or touching the case. Try to determine if the sound is coming out of the case or just in that area.
 

Hammermechanicman

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I would remove the spark plugs and the drive belt and clutch if it has one and the engine shroud. Then i would slowly rotate the engine checking for a tight spot or anything rubbing. Then spin a little faster and listen for the noise.
 

Hayward51

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Is your stethoscope solid on the end like the one I have? If so, listen to the case in that area, then use a hose in the same area to see if the sound is louder or softer near the case or touching the case. Try to determine if the sound is coming out of the case or just in that area.
Yes, it is solid on the end. I'll check it out again tomorrow. Thank you for your help. I can't think anymore for the frustration.
I would remove the spark plugs and the drive belt and clutch if it has one and the engine shroud. Then i would slowly rotate the engine checking for a tight spot or anything rubbing. Then spin a little faster and listen for the noise.
I have the engine 'uncovered' but no noise with spark plugs out. I only hear it after it starts.
 

bertsmobile1

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If the engine is working fine then don't go chasing ghosts
It could be the crankcase vent or the vent gasket, the fuel pump vent or any one of 1/2 dozen gaskets that are a tiny bit too big / too small or out of place
Could be the dip stick tube , could be a missing / out of place blade on the fan , a crack in the blower housing etc etc etc
 

Hayward51

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If the engine is working fine then don't go chasing ghosts
It could be the crankcase vent or the vent gasket, the fuel pump vent or any one of 1/2 dozen gaskets that are a tiny bit too big / too small or out of place
Could be the dip stick tube , could be a missing / out of place blade on the fan , a crack in the blower housing etc etc etc
Thanks for that ! I'm really tired of chasing ghosts. I've practically rebuilt this engine twice looking for this strange noise. The engine seems fine other than, who wants to buy an engine that sounds like that ?
 

Hayward51

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Thanks to all who tried to help. I can only hope the engine stays together until I get it broke in. I need to sell it for the parts money, at least, whistling and all ...
 

sgkent

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maybe if you recognize the tune it is whistling it will reveal itself.
 
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