Another engine mount question
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Joined: Aug 2004
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Another engine mount question
Please excuse another dumb question but..............Whats the difference between the "Urethane Motor Mounts" and the "Safety Engine Mounts" as advertised for example by Ecklers? What is meant by "safety mounts" are both required or are these just two totally different styles of mounts?
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Joined: Nov 1999
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From: Foxfield CO 1970 Convertible
The urethane refers to the cushion material between the steel plates on the mounts. Stock was plain old rubber.
The "Safety" mounts are made so the steel of the mounts interlocks with about 1/4 to 1/2 inch of play. If a mount ever breaks, the engine can't move more than about 1/2 inch. Without this interlock, the engine could (in theory) move several inches up and down, or twist somehow and come completely off the mounting area.... I think most Vettes since about 1969 have the locking engine mounts.
The "Safety" mounts are made so the steel of the mounts interlocks with about 1/4 to 1/2 inch of play. If a mount ever breaks, the engine can't move more than about 1/2 inch. Without this interlock, the engine could (in theory) move several inches up and down, or twist somehow and come completely off the mounting area.... I think most Vettes since about 1969 have the locking engine mounts.
Le Mans Master
Joined: Mar 2004
Posts: 7,458
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From: Little Rock AR
Safety mounts are not a bad idea. You can install two or just the driver's side. That is the only one that matters.
If you want to modify the plain old rubber mounts for safety you can drill a hole through the mount and install a bolt with a nylock nut left a few turns loose. The bolt will do the same as the safety mount. Still allows the engine vibration to be cancelled because the nut is not tight against the mount. I have not ever done this but I have heard it will work. I did once break a non-safety mount before and it was SCARY
-Mark.
If you want to modify the plain old rubber mounts for safety you can drill a hole through the mount and install a bolt with a nylock nut left a few turns loose. The bolt will do the same as the safety mount. Still allows the engine vibration to be cancelled because the nut is not tight against the mount. I have not ever done this but I have heard it will work. I did once break a non-safety mount before and it was SCARY
-Mark.
Le Mans Master
Joined: Mar 2004
Posts: 7,458
Likes: 1,484
From: Little Rock AR
They are not solid, they have a free metal tab that will hang up on the other half of the mount if the rubber breaks. You can see it when you take it out of the box. This is nothing to concern yourself about. GM installed the safety mount if your original mount went bad during the warranty period. Relax and install it. 
One of the biggest recalls in history was the defective non-safety style rubber motor mount. GM installed a cable to restrain the engine if your mount was still functional. The number of affected cars was staggering.
-Mark.
One of the biggest recalls in history was the defective non-safety style rubber motor mount. GM installed a cable to restrain the engine if your mount was still functional. The number of affected cars was staggering.
-Mark.
