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258 swap

Hello all- Currently I am replacing a 151 wutg a 258 w/T5/Dana 300 into a CJ7 and seem to running into an issue. Once the Transmission was bolted onto the crossmember bracket and I came up to take a look it was apparent that the engine was tilted back, so much so the valve cover is resting against the back of the engine compartment. It seems that the engine needs to be lowered to the same plane as the Transmission however this is several inches. I have several thoughts such as 1) This Trans for some reason doesn't work with the 258 2) There may be another crossmember bracket that raised the TM/TC (not likely) 3)The chasis engine mount brackets are bolted in the wrong place/wrong sides of the chassis or I do not have the correct one2 (bought from reputable 4wd dealer and said they came from a CJ w/258). This is my first attempt at rebuilding and am certainly hoping that I made a novice mistake. Any guidance, pics of 258 chasiss engine mount brackets, would be extremely appreciated. Thank you!

Reply to
CJ7 MrBeans
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Are you re-using the motor mounts from the 4 cylinder? They will cause that problem.

You need the correct mounts for the 258 (4.2l).

Spdloader

Reply to
Spdloader

Stock you only have about 1/2" clearance from the top back of the valve cover to the firewall. The engine does tilt back.

I have the same setup in my 86.

Could your body tub have shifted and not be bolted on right? This happens to mine now and then. I have to loosen off all the mount bolts and shift the tub back square.

When square, the back of the tub should just overhang the rear cross member slightly I believe. That is where I have mine set which makes my clutch linkage set up right also.

On mine, the firewall bottom is flush with the front frame mount's front.

Does the drain hole on the D300 line up with the hole in the skid plate?

Here is a photo of my tranny mount:

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It goes in the last set of holes in the skid plate.

I could take a photo of the mounts and put it up if you need.

The mounts are drawn in the Haynes manual on page 2C-7.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

Reply to
L.W. (Bill) Hughes III

This is a good point. I have not looked into this but for a few years in early 80's Jeep used a GM 151 and it is not same engine as later AMC 2.5. The AMC 2.5/150 was designed with same bellhousing bolt pattern as GM 151 but not sure about mount hieght. The 151 has a cross flow head and AMC 150 has intake and exhaust manifold on same side (it is based off of a cut down 258 with bore and stroke tweaded too but is does not share 258's bellhousig bolt pattern)

----------------- TheSnoMan.com

Reply to
SnoMan

Hello Mike- Thanks for your reply. I included an ablum with pictures of the engine chassis mounts, transmission mount, and a pic of how the engine is tilted against the firewall. The Dana 300 drainhole does line up in the skid plate and the Trans mount is in the last set of holes in the crossmember. I'll need to check the sqareness of the body tub.

In the pics the larger of the two chassis mounts is used on the passenger side and the smaller mount with the slit is being used on the driver's side.

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If you don't mind taking a picture of your engine chassis mounts and where they are bolted into the chassis that would be helpful.

Thanks again!

Reply to
CJ7 MrBeans

Hello- The 151 motor mounts were removed and I purchased some mounts that should be for the 258. Some pics included. Thanks for your comment.

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Reply to
CJ7 MrBeans

Those look like the four cylinder mounts to me.

I'll get a closer look at mine tomorrow in the light.

Spdloader

Reply to
Spdloader

Reply to
Greg

You have 1" engine lift mounts in there. You would need a 1" body lift to use those. The valve cover will hit. These are used for adjusting the driveline with lifts. Or you just have the wrong ones...

The proper mounts only have about 1/2" of 'rubber' sandwiched in there.

Look near the bottom of this webpage for a photo of one of mine I blew up:

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I will go look at mine tomorrow to verify the metal pieces, but the mounts are wrong.

Mike

Reply to
Mike Romain

Your steel mounts look the same and are mounted the same as mine.

The only difference is your really tall front rubber mounts, they are not correct. The tranny mount is correct.

The proper ones like the one on my photo link have the safety hook loop facing up on the passenger side and down on the driver's side. This prevents the torque from instantly tearing them in half.

Here is a CJ7 258 mount.

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The OEM ones from the $tealership are the best! I tear the crap out of and just plain shatter aftermarket ones...

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

Hi Greg- Sure if its not too much trouble. Thanks.

Reply to
CJ7 MrBeans

Here you go:

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For the driver's side.
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Passenger side
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Valve cover clearance of about 1/4" or so.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's - Gone to the rust pile... Canadian Off Road Trips Photos: Non members can still view! Jan/06
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(More Off Road album links at bottom of the view page)
Reply to
Mike Romain

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