How strong are the FE motor mounts on my F250?

[robroy]

Hi Folks!

Recently I've heard stories about guys who installed really powerful engines in their cars and wound up breaking their engine mounts (because of the torque).

Does this ever happen to our trucks? Could I run in to any problems with my new 390 (465 ft/lb @ 4,000RPM)?

Thanks!
-Robroy

[Jake11]

There pretty strong. If ya got more power than normal, get a chain and bolt it between the frame and motor on
the driver side. Just a little slack in it. Then the motor can't go nowhere when it twists. Jake

[FORDification]

As long as you're not revving the engine to the moon and then side-stepping the clutch to show off to the crowd, your mounts will be fine.

[willowbilly3]

I've broke a lot of the old non captive mounts, even on a 300-6 They break. If you have a high torque engine you may need to improvise something to hold it down.

[robroy]

Hi Jake, WillowBilly3, and Keith,

It sounds like I won't have much of a problem if I drive with a reasonable amount of care. I've always been interested in driving smoothly and not putting any undue, sudden stresses on the vehicle, so perhaps this won't be an issue for me. For example, I have never "popped" a clutch or done a Burn Out before.

Based on the way I hear some folks talking, it sounds like it's quite easy to break engine mounts with a powerful engine installed, but maybe they were driving roughly.

Are car engine mounts known to be generally weaker than those in our trucks?

Thanks very much folks!
-Robroy

[kaptnkaos]

Hey Robroy...

Look at a motor mount sometime...
They are like a sandwich.. 2 pieces of steel with a chuck of rubber in the middle.
What usually happens is that the rubber breaks loose from the steel on one side or the other.
This usually occurs when they get old and weak.
To prevent you can chain it down on the driver's side like Jake said.
I saw a really nice set up done with with an eye bolt through the frame and a chain bolted to the engine.
Use a turn buckle to connect the two, then you just tighten it up to remove the slack...
It's a sweet set up that doesn't cost hardly anything to do...

KaptnKA S

[sideoilerfe]

I've broken 3 of them. They're not that expensive. Your local parts store should have them, mine does.I would replace both of them when you install the engine to be on the safe side. Also, check and make sure the towers are tightened down. You should be fine after that.

Using a chain is pretty ghetto. It works but it might damage the tower.

[fireguywtc]

I have pulled the bolt and washer throught the drivers side mount tower when I put my motor back in after rebuild some years ago. It did no damage to the mount at all, they are tough. The motor twisted and the mount stud landed on top of the tower instead of back in the hole. It put everything in a bind. I had to lift the motor again to get it back in and fix everything. What a pain. The whole thing was my fault using the wrong bolts and lacking the foresight to see that happening But still to pull metal through metal they are tough, and when I pulled the motor out a couple of weeks ago they look almost new.

[robroy]

Hi Kaptnkaos, SideoilerFE, and FireguyWTC, thanks for responding!

KaptnKaos, I see what you mean about the construction of the mounts. As for installing a chain kit, I suppose I'd need to see a photo of an installation to really understand how they're attached, but that does sound like it could be a good idea.

SideoilerFE, I'll definitely be installing with new mounts! It's not so much the cost of the mount if it needs replacing that concerns me--it's the time and trouble it takes to replace them once the engine's installed. I don't have the very best in the way of facilities (working out in the dirt). I agree that the chain idea does sound a little ghetto, but maybe if I saw a clean implementation I'd change my mind about that.

Also, SideoilerFE, how did you break your mounts? What were you up to when they broke?

FireguyWTC, that does sound like the towers are tough!!! Maybe I should pick up some grade 8 hardware for the nuts and washers. As for the bolts, aren't they part of the engine mount? I could be remembering incorrectly.

So it sounds like the mounts are indeed breakable in various ways. Although I'm inexperienced with this topic, it seems like the same engine mount could be constructed using stronger materials and sold to folks with performance engines. I see some mounts like this in the Summit catalog, but maybe they also introduce more vibration in to the frame. What are your thoughts on this?

Thanks very much folks!
-Robroy

[fireguywtc]

Robroy, I was fefering to the mounts being tough but the towers are tough too. When I pulled the bolt through I was talking about the stud that sticks out of the mount through the tower. I did do some minimal damage to the hole in the tower mount when it came out, but mostly I damaged the washer which was an incorrect one when it came through. It was my fault, and I was 18 with few mechanical skills and knowlege. When the stud was resting on top of the mount tower I had to drive like that for a while and it did nothing to the mount so all in all they are super tough to me. Sorry for the poor discription, it's hard sometimes to write it then say it.

[kaptnkaos]

Hey RobRoy...

Yup, I know that feelin'... tryin' to work on yer truck on the ground.
it really does take a lot of the fun out of it.
Under normal conditions, both the mounts and the towers are plenty strong, and take alot of abuse...
I've had 2 '68's both had 390/Np435 set ups in them (an F-100 and F-250).
I have used and abused both of them, and have never broken a mount.
The '71 F-250 I bought a couple of years ago had a broken mount which makes me wonder what the PO did to break it.
I replaced the DS mount in it. It went pretty easy.
Best advice I can give you on that it to get as much clearance as possible to get the mount bolted to the engine... there isn't much working room there at all.
The hardest part was getting the bolts started 'cause they sit in a recessed hole with rubber all around it so you can't get yer fingers and the bolt deep enough to get the bolt started.
Something I found that helped alot was a deep socket with a thumb rachet.
If yer not familiar with them, they are small, flat, round ones (no handle) that fit well into tight places.they really come in handy in tight spots. Harbor Freight has a set of three (1/4, 3/8, 1/2 drives) for around $10. They go on sale regularly for around $5.
I think that all the major tool guys carry them as well, more expensive, but better quality I'm sure (though I have not had any problems with the ones I got at HF a couple of years ago).
I have also heard of, but never seen, soild mounts. They are made to the same deminsions as the rubber mounted ones, but are soild steel... no brakage for sure.
The chan set up I saw was pretty slick.
It had a piece of flat stock with a chain welded to it. That mounted to the engine using one of the existing holes for the PS or A/C braket.
There was an eye-bolt bolted to the either the cross member or the frame rail (I can't remember exactly)
There was a turn buckle that connected the chain and the eye-bolt together.
I didn't think it looked hokey 'cause it was a nice clean install.
Unless you are making extremely high HP, and driving it really hard, you should not need to do any kind of modification at all.
Now if I was buildin' a pre-runner like Ryan, I would give serious thought about installing a chain or cable setup or soild mounts, 'cauise I would not want my engine jumpin' on me cuttin' the rad hose and killin' the rad on me.

KaptnKA S

KaptnKA S

[DuckRyder]

Mine lasted about 575 miles and I haven't side stepped the clutch , although it will cover the entire bed of the truck in tire smoke shifiting to second.

Consideing it has 215/75/15 wranglers on it, I would expect the motor mount to last longer, I'm hoping it was just a poorly made fluke...

If another one goes I'm going to drill two holes through it and put a couple of aircraft grade bolts through the third one.

[sideoilerfe]

SideoilerFE, how did you break your mounts? What were you up to when they broke?

The one on the hi-boy i was doing some wheeling but nothing out of the ordinary. The 72 Camper special, same thing the first time. The second time, I noticed the towers were loose and I think it just got a little slack and ripped the rubber apart.

[ezernut9mm]

For example, I have never "popped" a clutch or done a Burn Out before.


-Robroy

wha? seriously? please find a deserted parking lot or back road and do one!

http://www.youtube.com/watch?v=28gtzOJdHqg

it is quite fun when, like all things, enjoyed in moderation....



...i am just pullin' your chain, but really, never?

[kaptnkaos]

This one's pretty sweet too EZ...
It has ta be an auto trans for this to work tho...

http://www.youtube.com/watch?v=NaOrr6kBe7U&NR=1

KaptnKA S