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Discussion Starter · #1 ·
Originally I had planned to use the P-30 motor mounts. After reading up on the mount problem here I am now confused.

1) If I run an A/C can I use the front mounts? From what I see those with A/C are using the Dodge setup. Is there any other available bracketry to mount the A/C so the P-30 front mount could be used?

2) If I run the Dodge setup what do I all have to get from the donor? Dodge Cummins parts are hard to find in the St. Louis area. So far I have not located any parts trucks.

3) Does one mount location allow more vibration than the other? It seems that with the front mount the weight of the engine is spread between the motor mounts and the trans mount. With the center mount the whole weight of the motor is right on them without any distribution to the trans mount.

4) I am not this far yet so I have an easy question. Is the motor mount bolt pattern the same on the front and center? Meaning can I put my P-30 front mount on the center location.
 

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The font mount looks live a v there is only one small rubber isolator ,but they where mahe to use a bellhousing mounts like the SAE .So you just couldn't just the front,you'll need to run some side mounts mid,or rear.

I will post up a pics of the front mounts,

Thanks
CrewCab59
 

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mid mounts

I fab my own mounts mid engine. Get a 3" by 3/8" plate. Drill the same 3 holes up front then put a heavy angle on two of the holes in block part way back. Then just butt weld it to the back of the plate. Get your weight centered on mounts. I've had trouble with the mounts up front. Thy do make for more viberation and I've broken all the bolts out of the bellhousing and the flex plate. The engine should balance on the mounts without a tranny. I've come to this conclusion and told a friend that was putting one in a ford van. He called me up and was so happy with the finish product. It works! On the AC I've always put them on top the alternator. Dont let people tell you that you cant reroute sepintene belts. I've done it 6 times and counting. Its very rewarding. Just mock it up and test run and adjust then finish welding and bracing. Put heavy angle under the base of the alternator mounting bracket and put your bolts all the way thought the angle. Use that for the start of your AC mount then brace it to the bottom close to the front of the mount. For the belt configuration come up from the crank on drivers side over the fan mount, under the tentioner pulley up over AC pump down to water pump and back up to alternater then down to crank pulley. And then I've always ran electric fan to be safe. Actually I've only put fans on just before I give the truck to the customer to be safe. I,ve run with no fan on the mountains and never needed a fan at all! They dont make much heat.
 

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Discussion Starter · #4 ·
The font mount looks live a v there is only one small rubber isolator ,but they where mahe to use a bellhousing mounts like the SAE .So you just couldn't just the front,you'll need to run some side mounts mid,or rear.

I will post up a pics of the front mounts,

Thanks
CrewCab59
I wasn't very clear with my questions. I had forgotten about the extreme front mount. When I said front mount I was actually talking about the forward of the 2 side mounts. I can understand why the very front mount couldn't be used. My question really is, "Is one of the side mounts was better than the other?"
 

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Discussion Starter · #5 ·
I fab my own mounts mid engine. Get a 3" by 3/8" plate. Drill the same 3 holes up front then put a heavy angle on two of the holes in block part way back. Then just butt weld it to the back of the plate. Get your weight centered on mounts. I've had trouble with the mounts up front. Thy do make for more viberation and I've broken all the bolts out of the bellhousing and the flex plate. The engine should balance on the mounts without a tranny. I've come to this conclusion and told a friend that was putting one in a ford van. He called me up and was so happy with the finish product. It works! On the AC I've always put them on top the alternator. Dont let people tell you that you cant reroute sepintene belts. I've done it 6 times and counting. Its very rewarding. Just mock it up and test run and adjust then finish welding and bracing. Put heavy angle under the base of the alternator mounting bracket and put your bolts all the way thought the angle. Use that for the start of your AC mount then brace it to the bottom close to the front of the mount. For the belt configuration come up from the crank on drivers side over the fan mount, under the tentioner pulley up over AC pump down to water pump and back up to alternater then down to crank pulley. And then I've always ran electric fan to be safe. Actually I've only put fans on just before I give the truck to the customer to be safe. I,ve run with no fan on the mountains and never needed a fan at all! They dont make much heat.
I photo is worth a 1000 words. Have you posted a photo of that here? If not could you? Thanks!
 

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O.K. Guys...This is a great topic, but I thought a picture would help a bit.
I'm in process of Motor Mounts at the moment. For my particular build (84 Ramcharger) don't want to move the forward, so I had planned on using the front mounts(Circled in Red).



Are these o.k. to use? That's how they are mounted in the P-30's.

Cumminsman. Are you using a combination like what I have circled in Blue?

Thanks for the insight.

Andrew
 

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Discussion Starter · #7 ·
From what I understand he is using the ones circled in green.
I just got back from the local salvage yard. I was hoping to find a 5.9 to take the A/C parts from. No luck and no suggestions on where to go.
 

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O.K. Guys...This is a great topic, but I thought a picture would help a bit.
I'm in process of Motor Mounts at the moment. For my particular build (84 Ramcharger) don't want to move the forward, so I had planned on using the front mounts(Circled in Red).



Are these o.k. to use? That's how they are mounted in the P-30's.

Cumminsman. Are you using a combination like what I have circled in Blue?

Thanks for the insight.

Andrew
Yes what you circled in BLUE is what I use. And I dont have any pictures to post. Sorry to busy to think of potograhing. I can try to do that on my next one. Your lucky to hear me on line becuse of my work. But when I do I start to get hooked on the things you guys are working on. I work 50 hours a week and build trucks by moonlight. Rememder the best trucks arent bought there built.
 

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BINGO!
Does one mount location allow more vibration than the other? It seems that with the front mount the weight of the engine is spread between the motor mounts and the trans mount. With the center mount the whole weight of the motor is right on them without any distribution to the trans mount.
The engine should balance on the mounts without a tranny. I've come to this conclusion and told a friend that was putting one in a ford van. He called me up and was so happy with the finish product. It works!
You've hit onto why my rear mounting works so well.
Like I've said before my side mirrors do not shake at all. My engine does not shake the truck when it comes to a stop and I only paid about $18 per mount from NAPA for the standard 6BT 1st generation Dodge truck square mount. I don't know what fluid mounts cost but I'm sure they are a lot more than what I paid. I don't think you have to go to fluid mounts to control your vibrations.
I also think that if you try and get as much of your engine weight on the front mounts you cancel out more of the vibrations that narrow spaced rear transmission mounts cannot.
I have my engine mounts are just in front of and almost touching the starter motor on the passenger side. The driver side mount is the same distance behind the front of engine as the passenger mount. You can see my mounting plates at my truck build postings. I don't think you need fluid mounts. I would also suggest bolting on a long backing plate outside of your frame rails if you have a C frame. My mounts are behind the main engine compartment cross member and I used long outside plates to to extend the forces back up to the main cross member to cancel out any frame twisting
 

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Discussion Starter · #10 ·
I work 50 hours a week and build trucks by moonlight. Rememder the best trucks arent bought there built.
You are a lucky guy. 50 hr is a very short week for me. I know all about the moonlight hours spent in the garage.

I didn't think these were what cumminsman was talking about because he said he starts with 3" x 3/8" plate. Now it finally soaked in. 3" wide x 3/8" thick and as long as you need to reach all the holes (not 3" long). Is 3/8" thick what everyone else is using? I have some 3" but it is only 1/4" thick. I don't think that is enough.
 

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I'm going to go with 1/4", I think. I started working my mounts last night. I'll post some pics, when they are further along.

Thanks for the info guys!
Andrew
 

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mid mount

When I used the plate it left me room to move the shelf that sits on top of the mount up and down till the motor hieght was right then I tacked it with the mig and got it setting on the mount. Repet on the other side, stand back and eyeball before finish weld. Ive often use 3/4 board strips to space pan and tight areas to keep from touching. Then remove when you set it on the mount to eyeball. Otherwise you will get to the finish product and when you downshift you hear that metel on metal sound.
 

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Discussion Starter · #13 ·
I started building the mid mounts. I have the angles for the rear holes on. The plate that bolts to the front 3 holes is welded to that. I added another brace behind the plate to tie it into the angle. The hardest part is cutting for the clearance around the oil return tube for the turbo. I added another bolt on piece that goes above the turbo oil return tube. I thought the mount looked a bit weak with the small amount of weld holding the plate to the angle on the turbo side. I would take photos but I am ashamed of how dirty it is under the motor on the floor. I still have the pan off the motor and it is still dripping. I got tired of wiping it up about a week ago. I'm used to the gassers. Their drippage isn't so black. Every time I touch this thing I am an oily mess.
Garden tractor pulling this weekend so no work on this until Monday. If your in Southern IL Friday or Saturday and want to see the hottest garden tractors in the country check out the Duquoin Fair Grounds .
 

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I went through the same issue with the oil return tube. Mine is the unpainted. Note the U cutout to clear the return tube.The grey one is the photo I copied from. My rear bolt holes are directly above my mount pads. You can see one of the posts peaking out in the pic.
 

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Yes thats the idea get the mounts back. But watch out for that starter. I made mounts in the truck once without a starter in place. It took up more room than I thought.
I think this is the reason for that extra pan reinforcement on the turbo 400 trans. They had those mounts to far front. It put to much weight on the bellhousing.I once put a 4BT in a with the 4L60E and used the bread truck mounts and he has trouble with snaping the bell bolts. He is trying right now to put the cast alluminum cover from a 4L80E from a new 6.0 that has the mounting area on the front of the cover to bolt to the bottom of the adapter plate.... Yes I did say 4L60E. Can't be more proud of the TCI control setup! The next one I'm going to use the 4L80E. The price of the control is right and you can change all your setting from your laptop on the fly. Took 20 min. riding in the passenger seat to get the thing tweeked. Man its cooool! Maybe I should put this in its on thread!
 

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O.K. Guys...This is a great topic, but I thought a picture would help a bit.
I'm in process of Motor Mounts at the moment. For my particular build (84 Ramcharger) don't want to move the forward, so I had planned on using the front mounts(Circled in Red).



Are these o.k. to use? That's how they are mounted in the P-30's.

Cumminsman. Are you using a combination like what I have circled in Blue?

Thanks for the insight.

Andrew
MY driver's side mount I used the 2 green sets.

For the passenger side I used the red area so I could clear the starter.

Any of them will work.
 

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Discussion Starter · #17 · (Edited)
Driverswanted, I was copying the mount you copied. I hadn't seen your photo with the pad just under the rear bolts. I am putting my pad like the other, just in front of the rear bolts. I haven't worked on these in a few days. The rubber mounts are here and waiting for my attention. You said you dirlled holes in yours?? How many holes? How big? Do you think that weekend them and shortened their life? Do you think they need them?? I have so many questions....
I did just buy a new a/c compressor on flea-bay today for $120 including shipping. It is the non-Dodge type Sanden with an 8 rib pulley. It has the ears sticking out from the compressor. It does have the easy to hook up tube fittings. I have some of these left over from some rod projects and they are easy to find.
Mooktank, I think it would be better to be a bit symetrical with the mounts. I don't know why. It just seems like the thing to do. The mounts are kind of like our hands. You wouldn't want a foot sticking out of one wrist.
 

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Good thread!
 
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