Engine Vibration

[prlee]

For some time I have been working on the high speed vibrations in the car. This has improved over the last year significantly. I now think whats left is to do with the rear wheels/tyres but I have also identfied that some of it is engine.

This is felt on the gear stick (its not from the box) and steering. I can feel it rising and falling with engine revs not road speed.

Question is is this normal and can it be reduced. I will be going over the engine tomorrow, checking distributor and carburettors as well as tuning and timing.

The car has a standard small bore mild steel exhaust system and the engine is completely standard.

Any thoughts?

Pete
1981 Carmelian Red 2 litre DHC.
Polybush, KYB shocks, electric fan, electric windows and electronic ignition roller bearing struts and anti-dive kit - otherwise standard
1979 Pageant Blue Spitfire 1500 - some restoration in progress.

[Milanoverde]

I'm thinking shifter bushings and/ or transmission mounts. Tony

[prlee]

Thanks Tony, but both have been replaced.

Pete
1981 Carmelian Red 2 litre DHC.
Polybush, KYB shocks, electric fan, electric windows and electronic ignition roller bearing struts and anti-dive kit - otherwise standard
1979 Pageant Blue Spitfire 1500 - some restoration in progress.

[FI Spyder]

There is going to be some engine vibration on a 4 cylinder engine of this vintage. Manufacturers struggled to minimize this in some engines with things like counter rotating balance shafts. I prefer to think of it as a desirable characteristic of the age kind of like when airline pilots climb out of their 747's and for fun go for a spin in their Stearman Biplanes.

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[kstrutt1]

They are not the smoothest of engines so some vibration is normal, check the engine to gearbox bolts and mount bolts are tight, beyond this if it running well there is little you can do, also it may improve when you fix the wheel imbalance, this can excite the engine on it's mounts.

[Hasbeen]

It could be an unbalance in the clutch gear.

Try hitting the clutch while going down a ling hill, then try with the thing in neutral, with the clutch in & out. If there are any changes to your vibration that should help reduce the possible causes.

Hasbeen

[prlee]

Didn't have the time I had planned today, to many other things needed doing.

However did try the engine in neutral clutch in and out and didn't notice any difference.

However I did take the cap off the distributor cap off and found the mechanical advance was very stiff and probably not working. Its either fully advanced or wont advance. This was not really a surprise as I found the same thing when I got the car.

I didn't have time to sort it this week, will have to wait to next weekend. Car runs ok but will not be on top performance, could this give rise to more vibration?

Pete
1981 Carmelian Red 2 litre DHC.
Polybush, KYB shocks, electric fan, electric windows and electronic ignition roller bearing struts and anti-dive kit - otherwise standard
1979 Pageant Blue Spitfire 1500 - some restoration in progress.