help with harmonic balancer?

[delta5]

Hi Everyone,
wonder if anyone can help with a vibration issue....getting a lot of vibration on start-up and increasing revs....once up to speed everything is nice and smooth...so im thinking its either the engine mounts have gone hard and need replacing or its the harmonic balancer that's not balancing anymore....

im ok changing the mounts but the balancer is another matter and can you get them from sunbeam specialties?....anyone done this replacement before?
thanks in advance....
David

 

[alpine_64]

David many of the modern mounts are to hard and cause vibration issues, change the mounts and see what happens. As for the balencers they often crack in the key way so check yours, does it have justva nut holding it on or the crank vhandle jaw? If the jaw nut replace with a standard nut as they are easier to torque .

If cracked fortunately there are now repros available from stock metal to lightweight alloy... I think one of the usa suppliers is listed on the home page

 

[90days]

Harmonic Balancers

I found a UK web site the sells new balancers and parts. Might be helpful?


http://rootesparts.com/id103.htm

 

[alpine_64]

I found a UK web site the sells new balancers and parts. Might be helpful?


http://rootesparts.com/id103.htm

They are Actually in the Netherlands, he'd be better off with the USA supplier given location .

http://www.bhjdynamics.com/index.php?main_page=index&cPath=25

 

[hartmandm]

The rubber is too hard from US suppliers of engine mounts - Sunbeam Specialties and Classic Sunbeam. Get the engine mounts from Rootes Parts in the Netherlands. I know from recent personal experience...

Mike

 

[George Coleman]

The Roots Post motor mounts are the ones to use, the others are to hard.

 

[delta5]

engine mounts for alpine

Hi Everyone,
thanks for the suggestions in regards to correct engine mounts...I took a look at the rootes Netherlands web site and am intrigued with their description of the mounts as not hard and not to soft,,,,,they seem like the right way to go but the site and ordering looks confusing and questionable.....is there not a place in the us that has the correct ones?
thanks,
david

 

[jumpinjan]

...or its the harmonic balancer that's not balancing anymore....

The pulley on the front of the crank's purpose isn't to dynamically "balance" the rotating parts. It's a "torsional damper" to dampen (hopefully) the torsional oscillations in the crankshaft (the twisting over the length of the crankshaft, is a sort of pendulum oscillator). Excitation frequencies (power pulses) can cause a resonance of the natural frequency (of the crankshaft), and if the energy isn't removed by some amount of dampening, the forces amplify to the point of material fatigue (it can break).
The four-cylinder configuration is not as perfect as the six-cylinder configuration as it will produce some rocking moments. That's probably the shaking that you might feel. Yeah the motor mounts aren't the best design. Today's engines today use a viscous damping type of engine mount (Usually one of the three mounts, I think), and they do work pretty well.
Jan

 

[hartmandm]

Hi Everyone,
thanks for the suggestions in regards to correct engine mounts...I took a look at the rootes Netherlands web site and am intrigued with their description of the mounts as not hard and not to soft,,,,,they seem like the right way to go but the site and ordering looks confusing and questionable.....is there not a place in the us that has the correct ones?
thanks,
david

Nope. If you want to order the mounts, exchange e-mails with the gent in the Netherlands and you will get to an order.

Mike