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View Full Version : 88 LXi, only available motor mounts are too tall?



yyz123
07-27-2015, 12:38 PM
For 1988 Accord LXi w/ fuel injection & auto trans, the OEM Honda front and rear motor mounts are discontinued and all the aftermarket ones I have seen are 1/2" or so too tall, meaning the engine tilts up on the passenger side end about an inch because the left side mount secures the engine at a fixed height (it pivots upward from there). The hanger rubber mount on the right side then can't be connected (because the hanger spars are now too close together).

Original part numbers were:
Front 50810-SE0-J31 (I think superceded from original 50810-SE0-J30)
Rear 50811-SE0-980

Actual stock, correct distance from frame cross member to engine mounting bracket surface (means does not include stud height) is about 86mm for front and 73mm for rear. At first I thought the aftermarket ones were just higher because the old ones might be sacked out some but that is not the case, the new ones definitely jack the passenger side of the engine up. It seems some sort of part number convergence happened some time ago and they've all now got the wrong height ... well, they are the correct height for some other models no doubt, just not for 88 LXi automatic. You can even find (aftermarket) front ones on eBay with the correct Honda part number (according to the Honda catalog, of course this assumes the Honda part number didn't supercede to an incorrect number before the aftermarket copied it) molded into the rubber but with wrong height. I used "Anchor" brand but like I said others you can find look the same.

Anyone have the solution? If changing brackets is a possibility, I believe most or all from this era are also discontinued, so I guess that'd turn into a junkyard search ... although I've noticed around here (Los Angeles area) there aren't all that many cars in junkyards this old anymore, at least the yards I've been to ...

Thanks for any help

2oodoor
07-27-2015, 04:46 PM
If you can find it, in the original shop manual for these cars it has a procedure for a sequence of how to properly center the mounts to aleve vibrations etc.. I have never gone by that procedure but I do leave the left side mount up by the timing cover loose so I can get the others in and level the engine up. That one seems to be capable of multiple positions. Have all the bolts in and started just not tightened so you can move things around and not have to line up bolt holes which is a pain.

yyz123
07-28-2015, 01:22 PM
If you can find it, in the original shop manual for these cars it has a procedure for a sequence of how to properly center the mounts to aleve vibrations etc.. I have never gone by that procedure but I do leave the left side mount up by the timing cover loose so I can get the others in and level the engine up. That one seems to be capable of multiple positions. Have all the bolts in and started just not tightened so you can move things around and not have to line up bolt holes which is a pain.

Right, I do have the manual and follow the sequence. The problem is the too-high front and rear mounts lift the engine up and the vertical position of the left mount is fixed. (even if the left mount could move up so you could level the engine, the whole engine would still sit too high as compared to stock mounts and the right rubber trans hanger mount still could not be connected)

cygnus x-1
07-30-2015, 08:01 AM
The height of the available aftermarket motor mounts (for the front) is definitely a known issue, although I didn't know that the rears were also too tall. The issue with the front is that there are two different mount types, a tall and a short. The tall exists on the 88-89 LX-i/SE-i with the manual trans (and possibly automatic) and the short mount is for all others. The problem is that in the cross reference databases, the two get confused sometimes and people usually end up with the tall mount when they need the short, so the engine sits too high in the front.
From what I understand the rear mount should be about 75mm tall and the front mount should be either 75mm or around 100mm. I'm less sure about the front since I've not personally measured a known OEM mount (as opposed to an aftermarket).

Anyway the reason I know all this is because I designed an adapter bracket that converts an off the shelf GM transmission mount to work as a front or rear motor mount for the 3g Accords and 2g Preludes. It's intended to be a stronger (and stiffer) replacement for the factory parts; enough so that it lets you remove the dog bone (torque bar) mount completely. If you look in the custom fabrication section here you should find the thread about it.

C|

yyz123
08-02-2015, 08:34 PM
The height of the available aftermarket motor mounts (for the front) is definitely a known issue, although I didn't know that the rears were also too tall. The issue with the front is that there are two different mount types, a tall and a short. The tall exists on the 88-89 LX-i/SE-i with the manual trans (and possibly automatic) and the short mount is for all others. The problem is that in the cross reference databases, the two get confused sometimes and people usually end up with the tall mount when they need the short, so the engine sits too high in the front.
From what I understand the rear mount should be about 75mm tall and the front mount should be either 75mm or around 100mm. I'm less sure about the front since I've not personally measured a known OEM mount (as opposed to an aftermarket).

Anyway the reason I know all this is because I designed an adapter bracket that converts an off the shelf GM transmission mount to work as a front or rear motor mount for the 3g Accords and 2g Preludes. It's intended to be a stronger (and stiffer) replacement for the factory parts; enough so that it lets you remove the dog bone (torque bar) mount completely. If you look in the custom fabrication section here you should find the thread about it.

C|

Thanks. I definitely can't go with stiffer mounts as idle vibration especially with AC on is a concern (not terrible but not close to typical modern 4 cylinder expectations). In fact I only did the mount replacement more as an experiment to see if idle vibration would improve (if the old ones had gotten harder over time). It's about the same now but "different" (the overall vibration level is comparable, but the feel and which interior parts shake or buzz changed a little). So I would go back to the old ones to properly level the engine since I'm selling it now (not related to this, just got another car by coincidence at this timing), but I damaged the front. Wonder if I can find a good used "short" front one?

This vehicle (88 LXi fuel inj, auto) does have a cast front bracket. Some posts suggest that bracket takes the "tall" front mount, but if the tall mount is 100mm, then it is definitely too tall.