Engine mount help needed please.
#1
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My 1998 Cobalt 252 came with a 502 MAG from the factory. It used factory engine mounts.
I am going to be installing a 502 NA engine making somewhere in the 550-575 HP range. It was suggested that I upgrade the engine mounts.
This is my bilge. As you can clearly see, I do not have the typical vertical stringer arrangement like most of you on here.

I purchased an offshore style engine mount to use, but am not sure how to configure it with my set up?
This is the mount I have.

I came across these side brackets on Teagues Custom Marine site but am not sure which bracket to get, or how to actually install it.
https://teaguecustommarine.com/engine-mounts
Does anyone have a pic of a similar set up that would help me understand what it is I need to get?
OR....
The other option would be the billet replacement mounts from Hardin
https://www.cpperformance.com/p-1353...ine-mount.aspx
Or the Eddie Marine ones.
https://www.summitracing.com/search/...-engine-mounts
I'm hoping to get parts in hand, so when the engine is ready, it can get a move on.
Thanks for any help
I am going to be installing a 502 NA engine making somewhere in the 550-575 HP range. It was suggested that I upgrade the engine mounts.
This is my bilge. As you can clearly see, I do not have the typical vertical stringer arrangement like most of you on here.

I purchased an offshore style engine mount to use, but am not sure how to configure it with my set up?
This is the mount I have.

I came across these side brackets on Teagues Custom Marine site but am not sure which bracket to get, or how to actually install it.
https://teaguecustommarine.com/engine-mounts
Does anyone have a pic of a similar set up that would help me understand what it is I need to get?
OR....
The other option would be the billet replacement mounts from Hardin
https://www.cpperformance.com/p-1353...ine-mount.aspx
Or the Eddie Marine ones.
https://www.summitracing.com/search/...-engine-mounts
I'm hoping to get parts in hand, so when the engine is ready, it can get a move on.
Thanks for any help
Last edited by xlint89; 01-12-2023 at 05:54 PM.
#2
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From: Wisconsin
Unfortunately you’re not going to be able to use the offshore style mount like in your second picture. You can replace your pedestal style mounts if they’re worn, otherwise I’d reuse them.
I get a kick out of how everything “billet” in the marine industry costs an arm and a leg.
I get a kick out of how everything “billet” in the marine industry costs an arm and a leg.
#4
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Use the cp performance solid pedestal mounts and as long as the "boxed engine mount platforms" are solid like diamond mentioned, then i would;
cut and pre drill a piece of 1/4 aluminum plate with rounded corners that just fit in the wrench slots, fish them in with string till you get 1 nut and bolt installed. This will have substantially more clamping force than the washers that are most likely in there and squished into the underside.
Return the offshore plate, hopefully no re stock fee, shipping will kill ya tho
cut and pre drill a piece of 1/4 aluminum plate with rounded corners that just fit in the wrench slots, fish them in with string till you get 1 nut and bolt installed. This will have substantially more clamping force than the washers that are most likely in there and squished into the underside.
Return the offshore plate, hopefully no re stock fee, shipping will kill ya tho
#6
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And to add some info.
No moisture problems at all with the stringers/mounts. They are fiberglass hollow bases with 1 side having 1 1/2" of wood glassed over. And the other side has 2" of wood glassed over.
If you look at the pic of my bilge on the inside of the bases you can see a piece of tape. That was used to hold the "plug" in place until the silicone set up.
The lag bolts that held the motor mounts down had stripped out. I drilled an access hole in the bases and installed stainless fender washers and bolts from the bottom.
No moisture problems at all with the stringers/mounts. They are fiberglass hollow bases with 1 side having 1 1/2" of wood glassed over. And the other side has 2" of wood glassed over.
If you look at the pic of my bilge on the inside of the bases you can see a piece of tape. That was used to hold the "plug" in place until the silicone set up.
The lag bolts that held the motor mounts down had stripped out. I drilled an access hole in the bases and installed stainless fender washers and bolts from the bottom.
#7
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From: Murrayville Georgia
I have a set of the billet mounts for sale. they came with a bunch of stuff a friend wants to sell as he got rid of his boat. I dont know if they were even installed but do have a few nicks from bouncing around the shelves. $100 plus the shipping if your interested.


#8
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Don't be disappointed, this is good news, it's a money saver for ya. Only time you'll see that fancy offshore plate is when it's in your way trying to work on something or clean the bilge.
A 2 inch (or any appropriate size) hole saw makes great 1/4 inch thick aluminum washers too ! Drill the pilot hole out to whatever size bolt being used.
i like plates best but whatever fits sometimes has to be best, way better than washers for sure.
Think standing on thin ice or standing on a sheet of plywood on thin ice.
my opinion, Compedge marine has a good deal on those pedestals, especially if they come with those cast mounts.
paint to match or pop.
A 2 inch (or any appropriate size) hole saw makes great 1/4 inch thick aluminum washers too ! Drill the pilot hole out to whatever size bolt being used.
i like plates best but whatever fits sometimes has to be best, way better than washers for sure.
Think standing on thin ice or standing on a sheet of plywood on thin ice.
my opinion, Compedge marine has a good deal on those pedestals, especially if they come with those cast mounts.
paint to match or pop.
Last edited by outonsafari; 01-12-2023 at 10:33 PM.
#9
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I have a set of the billet mounts for sale. they came with a bunch of stuff a friend wants to sell as he got rid of his boat. I dont know if they were even installed but do have a few nicks from bouncing around the shelves. $100 plus the shipping if your interested.


#10
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Don't be disappointed, this is good news, it's a money saver for ya. Only time you'll see that fancy offshore plate is when it's in your way trying to work on something or clean the bilge.
A 2 inch (or any appropriate size) hole saw makes great 1/4 inch thick aluminum washers too ! Drill the pilot hole out to whatever size bolt being used.
i like plates best but whatever fits sometimes has to be best, way better than washers for sure.
Think standing on thin ice or standing on a sheet of plywood on thin ice.
my opinion, Compedge marine has a good deal on those pedestals, especially if they come with those cast mounts.
paint to match or pop.
A 2 inch (or any appropriate size) hole saw makes great 1/4 inch thick aluminum washers too ! Drill the pilot hole out to whatever size bolt being used.
i like plates best but whatever fits sometimes has to be best, way better than washers for sure.
Think standing on thin ice or standing on a sheet of plywood on thin ice.
my opinion, Compedge marine has a good deal on those pedestals, especially if they come with those cast mounts.
paint to match or pop.


