| Author |
Message |
    
Pete Burgess
Experienced User
Username: pburgess
Post Number: 6
Registered: 11-2003
| | Posted on Friday, 23 January, 2004 - 20:40: |    |
There have been articles recently about front engine mountings allowing fans to meet radiators. Mine recently has, causing a nice scrape at about 11 o’clock but not making anything leak. How do you test the integrity of the front engine mount in situ, is it as easy to change as it looks, where is a good place to support the engine while changing it and what else could cause the fan to come forward if it’s not the front mount? |
Richard Treacy
Prolific User
Username: richard_treacy
Post Number: 93
Registered: 4-2003
| | Posted on Friday, 23 January, 2004 - 22:25: | |
To test or replace, simply place a hefty block of qood as close as reasonable to the front of the sump and jack it up. You will immediately see if the mount has sheared.
There should be a metal bracket to stop the motor moving forward if the mount is sheared, but I can imagine that the motor could bounce over that in an emergency stop. Not worth the risk.
Also check the rears as the same applies. A sheared rear LH mount can jam the steering column on a left hand drive Shadow II on overrun, and a low right hand one can jam the column on a right hooker when accelerating (I had that after fitting them too low on the chassis on my SZ).
Be safe: replace all the mounts if in aany doubt whatsoever. They are usually softened by oil anyhow (check that first). |
David Gore
Moderator
Username: david_gore
Post Number: 175
Registered: 4-2003
| | Posted on Saturday, 24 January, 2004 - 09:04: | |
Richard has raised a very relevant point about the positioning of the rear mounts as it is a normal reaction to set them as low as possible to maximise "clearance" between the transmission bell housing and the body however the proximity of the steering and accelerator linkages are not considered. I had a problem with the engine speed increasing whenever reverse was selected, the problem was caused by the engine/transmission torque reactions lifting a tired mount causing the accelerator linkage to move - this did not happen when the car was placed in drive as the torque reaction was not sufficient to move the linkage. New mounts and higher mounting position fixed the problem.
When replacing the mounts or allowing the engine to drop on the mounts to fix oil leaks from the rear cover plate on the engine, it is a good idea to disconnect the accelerator linkage betwen the body and engine to avoid damage. |
Bill Coburn
Grand Master
Username: bill_coburn
Post Number: 101
Registered: 4-2003
| | Posted on Saturday, 24 January, 2004 - 19:37: | |
David this still leaves a long unanswered question, how do you set the mounts? The manual directs scribing the bracket positions before removal but if this hasn't been done where do they go. The couple of times I have had this problem I have worked off the angular displacement of the front universal. |
Bob UK
Unregistered guest
Posted From: 195.93.33.11
| | Posted on Sunday, 25 January, 2004 - 09:27: | |
I have found that the adjustment is not critical and once new mountings are fitted everything lines up fine.
I put all three in place make sure the sitting square with the mountimg points by leaving all bolts slightly loose .
Tighten the front first then loosen the back off give the engine a shake and then tighten the bolts. I grease the backs so they will slip on loose bolts better.
The front one gets particular grotty. The engine will overide the safety buffer because is not actually a safety stop. It is part of the engine mounting system. This part should have a rubber strip on it which goes grotty as well. you can super glue rubber on this.
Shadow engines coming off the mountings under heavy braking is not unusual and the mounting seem to last around five years before they go off.
I fitted new ones last year and the car was much better for it.
If you do get a problem with alignment such as prop vibs check the final diff mountings first before you reset the engine mounts.
In theory the angle of the front uni should be the same as the rear uni.
However in practice the rubber mounting will totally absorb any vibs caused by SLIGHT propshaft misalignment. But if the final drive mounting are shot as well then although careful adjustment may cure the vibs the real culpit is the diff mountings have gone off. I suspect that like my car the diff mountings on most Shadows are 30 years old.
The throttle linkage is compensated by careful design to take account of engine movement which when under full load can be a lot. So that providing the engine is near enough in the right place it will be fine.
IF you think carefully about the tranmission of power to the road you will see that the even the tyres are absorbing transmission torsional vibs via the side walls and tread belt.
I find in general that when a car is fussy on setting up that something else is worn some where rubber mounting are a favourite.
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