Chev rear engine mount photos needed.

cliff · #1 06-04-13, 15:20

I am having trouble finding good clear views of the rear engine mounts and cross member on cab 11/12 &13 - C15, C15A, C30 and C60 model CMP's. Are they all the same or different?

Can anyone help with some clear photos and possibly a measurement or two?

This is to help correct a series of models of the above

Thanks in advance

Phil Waterman · #2 06-04-13, 23:29

Hi Cliff

I'll start off the answer to your question first two photos are of the rear engine mount as found on all trucks so that covers HUP, Pattern 13 C60S and Pattern 12 C60L. The picture is of a NOS set that I just picked up the picture is the illustration that came in the box.

The last picture is looking straight on with the engine removed on the Pattern 12 C60L.

Cheers Phil

cliff · #3 07-04-13, 00:16

Fantastic Phil that answers my question nicely thank you

BSM · #4 07-04-13, 07:13

Quote:

Originally Posted by Phil Waterman

Hi Cliff

I'll start off the answer to your question first two photos are of the rear engine mount as found on all trucks so that covers HUP, Pattern 13 C60S and Pattern 12 C60L. The picture is of a NOS set that I just picked up the picture is the illustration that came in the box.

The last picture is looking straight on with the engine removed on the Pattern 12 C60L.

Cheers Phil

Phil .... interestingly enough we were discussing this aspect this morning when we removed the nose in preparation for an engine change in the No.6. The point under discussion was that the earlier manual has the spring on the bottom per your drawing and the later 43 manual has it on the top. Any idea why the change?
Regards....Rod

Phil Waterman · #5 07-04-13, 14:48

Hi Rod

You raise an interesting point, you are correct MB-C1 shows the spring on the bottom while the MB-C2 shows the on the top. Wonder if the change is just something simple like one less thing sticking down to catch on brush.

I've tried to figure if there would be any difference to the reaction to engine torque trying to lift one side or the other of the engine. But I don't think it would make any difference.

Cheers Phil

Grant Bowker · #6 07-04-13, 15:09

Having the spring on top would maintain flexibility even if the bolt seized in the cross member.... but I doubt they would have been thinking of us 70 years in the future.

Phil Waterman · #7 07-04-13, 15:18

Hi Grant

Good point, but given the oil retention characteristics of Chevy engines how many engine mounts have you seen that don't have little drops of oil hanging from the engine mount bolts if they have been driven within the last year.

Cheers Phil

motto · #8 11-04-13, 02:56

I don't know the reason for the change in the location of the spring and was unaware of them ever being in the lower position.

On the L/L Chev which is what I am familiar with they used the same set up. If you look at the bolt in Phil's picture you will notice that it has a step in it adjacent the thread. On the trucks I've worked on I was sure that the lower hole in the crossmember was smaller and would only allow the bolt head and spring to be installed in the upper position. I've just been outside to have a look at a couple of crossmembers and find that I'm wrong in regards to those two at least. Was I imagining it?

David

rob love · #9 11-04-13, 03:10

Quote:

Originally Posted by Phil Waterman

Hi Grant

Good point, but given the oil retention characteristics of Chevy engines how many engine mounts have you seen that don't have little drops of oil hanging from the engine mount bolts if they have been driven within the last year.

Cheers Phil

A Ford man has found this amusing.

Lynn Eades · #10 11-04-13, 04:18

Rod with regards your question in post #4.
Here are some thoughts;
Maybe the reason for the bolt going from top (early) to bottom stemmed from the idea that it is better to have the bolt head at the top, where gravity tends to assist in keeping it (the bolt) in place. (if the nut falls off, which is better that loosing the bolt, when the nut falls off, from the top)
Then maybe, because of damage to the bolt (or an important mechanics head) and with ground clearance a consideration, a wise GM engineer (ex Ford)decided that with a castle nut and split pin, the bloody thing can't fall off, "so we will fit them the other way up" (good stories have happy endings)

BSM · #11 14-04-13, 08:54

Quote:

Originally Posted by Lynn Eades

Rod with regards your question in post #4.
Here are some thoughts;
Maybe the reason for the bolt going from top (early) to bottom stemmed from the idea that it is better to have the bolt head at the top, where gravity tends to assist in keeping it (the bolt) in place. (if the nut falls off, which is better that loosing the bolt, when the nut falls off, from the top)
Then maybe, because of damage to the bolt (or an important mechanics head) and with ground clearance a consideration, a wise GM engineer (ex Ford)decided that with a castle nut and split pin, the bloody thing can't fall off, "so we will fit them the other way up" (good stories have happy endings)

Lynn thanks for the comment. I can certainly see the logic in your observation and would agree in principle however and given the tubular configuration of the actual mounting I suspect that subsequent operational experience/s convinced some bright mechanical engineer that the optimum location for the spring was on the top.
No doubt an AEME/REME/Canadian Version official notification will surface in due course outlining the reason/s for the change. Always room for another little mystery!! Rod