SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: dustin on July 05, 2009, 07:33:37 PM

Title: motor mounts
Post by: dustin on July 05, 2009, 07:33:37 PM

Here it is. I have a 77 sundance with a 454 and berkley. Tha front motor mounts are in the same spot they would be on a car, with a mount on the motor that connects to a mount that bolts to the stinger. The back has a bell housing that bacically sits on the pump then has like a u clamp that holds it there. My buddy just bought a 79 miller that has plates on both ends of the motor then bolts right to the stingers. it looks like his motor is alot more solid then mine. When mine is idleing you can see it rock back and fourth, his doesn't move a bit. I'm now wondering if it's a big deal and if so should I change mine. He has full lenth stingers on his boat. Where on mine I don't. Maybe thats why the back of my motor is mounted to the pump, for more stability? Does any one know anything that can help me out?

Title: Re: motor mounts
Post by: Nordie on July 05, 2009, 08:05:11 PM

You can do motor plate on the front...in fact I like the idea of the plate...I had a cradle set-up in one of my boats and the rubber was all rotted out and I couldn't find new mounts so I had to fab them up! I guess the cradle has a perk of taking vibrations away and making a smoother ride! But I have seen 1/4 stringer boats with front and rear motor plates

Title: Re: motor mounts
Post by: IRRebel on July 05, 2009, 09:47:20 PM

Quote from: Nordie on July 05, 2009, 08:05:11 PM

You can do motor plate on the front...in fact I like the idea of the plate...I had a cradle set-up in one of my boats and the rubber was all rotted out and I couldn't find new mounts so I had to fab them up! I guess the cradle has a perk of taking vibrations away and making a smoother ride! But I have seen 1/4 stringer boats with front and rear motor plates

X2, I'm running cradle mounts (Solids) plus the "clamp around the pump" on the Moo with no real problems. Some of the mount bolts loosen after a good hard day of running, but have been replacing them with nylocks as I go. She's getting a front plate soon only to subside some of the shaking and rolling around the engine does (Mostly at or near it's rough idle), but this boat is to a somewhat extreme in this little boat with that much power. (I'm more concerned with the oil pan hitting the bottom of the hull, it is VERY close! And twists quite a bit under full power launches.)

Some boats came with the 4 point mounts standard. Sanger and Biesemeyer, to name a couple (Miller may have as well). Most did not, and unless a huge amount of HP is applied or the stringers are a little questionable (Whose aren't on 30 year old boats), then a rail system and 4 point is the way to go. (Or even 5 point, you can still bolt the bellhousing to the pump on a 4 point mount in most cases).

Hope this helps.

Ray

Title: Re: motor mounts
Post by: beerjet on July 05, 2009, 10:11:43 PM

If your not having any issues, leave it.
If you up the power substantially, change it.
Personally I dont like the 3 point system but swapping to motor plates is an unessicary (sp?) pain in the ass.

-beerjet-

Title: Re: motor mounts
Post by: GT Jets on July 05, 2009, 10:14:15 PM

For the record, not one of the sanctioning bodies allow three points for racing.

I have use Moroso solid motor mounts in place of the rubber mounts, they seem to take away a lot of slop...I think I have a set in the shed :thumbup:

The older ones used a set of factory style rubber tee mounts.....

GT

Title: Re: motor mounts
Post by: IRRebel on July 05, 2009, 10:59:40 PM

Quote from: GT Jets on July 05, 2009, 10:14:15 PM

For the record, not one of the sanctioning bodies allow three points for racing.

I have use Moroso solid motor mounts in place of the rubber mounts, they seem to take away a lot of slop...I think I have a set in the shed :thumbup:

The older ones used a set of factory style rubber tee mounts.....

GT

Glenn's right, but then again, we're talking lake boats here, and you're also required to wear a vest, restraints, helmets, etc during racing that we are not.  While we can argue that some of our boats are approaching and are at or over in performance of some of the racing brethren that inspired them, the same precautions on the " solidarity", if I may try and use the word, of the boat needs to be addressed.

I am a prime example, and shoulda known "This ain't no Chevelle or Gran Torino" when building my engine.  :banghead: (going through it AGAIN ,twice actually, and far more HP is on the charts for the next two boats). The Moo definately needs some support on the engine mounts. Everything else is fine, that I can tell, I just get nervous seeing that engine "shake rattle and roll". That's why the front plate.

On the other hand, Stock or mild motors? Run what she brung and have a blast!

Ray

Title: Re: motor mounts
Post by: dustin on July 07, 2009, 08:13:42 PM

Right on I think I may go with a plate in front and just leave the back alone. I'm not running much over 450 horse or so and don't plan on adding any. What about putting a stiffener on the out side of the stinger. I've saw a few people on here with those added to there boats.