Inlet Manifold Throttle Cam Binding

[caveman]

Part way through tuning my SU's, ive just noticed my inlet manifold throttle linkage is catching the engine frame.
It's the linkage cam/lobe that connects to the carburettor nearest to the bulkhead and the cam is clearly longer than the neighbouring linkage that attaches to the centre carb, which has plenty of clearance.

What stops the throttles at maximum open travel? (throttle butterfly/linkage etc?)
I've never had an issue with hard acceleration but note my accelerator pedal full travel is now being restricted by the frame.

My initial thoughts:

1. Engine mounts have gone soft? Looks like thay are standard rubber.
2. Engine/Gearbox stabiliser needs tightening (rubbers replaced last year)?
3. Gearbox rear spring gone soft? I think it's the original.
4. Inlet manifold casting is lower on bulkhead end (manifold was a replacement some years ago)? Unlikely as I seem to remember a small mark always being there in the paint and prior to its replacement.

Thoughts/advice welcome.

[tim wood]

Do you have the spacing plate sometimes fitted under the right side engine mount?
This is present to avoid the throttle linkage catching on the engine frame

Part number c18242


Tim

[caveman]

Hi Tim,
Many thanks, it looks like it is missing so just ordered along with uprated mounts

[abowie]

Replacing your engine mounts should fix this.

Also check that your engine isn't cocked right hand side down.

[caveman]

Thanks Andrew,

I'll get the spirit level onto it.

I've been trying to gain knowledge of the engine mount shim/spacers as they are sold in pairs.......should they be on each side to keep engine level or is it accepted that the engine sits higher on the RH side to maintain throttle/carb frame clearance?

[mgcjag]

Hi Steve...spacers were an "as required" item...Steve

[caveman]

Thanks Steve,
I’ll order a couple along with mounts and adjust accordingly once installed.

[mgcjag]

Carefull closeing the bonnet after fitting...the carb tops are close..

[caveman]

[caveman]

A quick update and thanks to those who took the time to reply to my original request.
Having just fitted new & upgraded engine mounts (M.Robey) I now have good clearance on the throttle cam. No shims were required (& none fitted originally):




Worth checking or replacing if you're using standard mounts:

[tim wood]

Those mounts look knackered !

As mentioned check carefully on carb to bonnet clearance ( although with products from Rob Beere you should be ok )