1987 Glassport 4.3 v6 swapped for 1991 Chevy C-10 4.3 v6

I recently took ownership of A 1987 Glassport cuddy. It was parked about three summers ago because the oil pressure dropped and the operator at the time shut it down. Got towed in land to his trailer. Inspected the engine area and found Oil. He got it trailered home. Hooked up the muffs and a hose. Fired it up and watched as the Oil pan shot Oil out. Left it go for almost three years. Oak leaves backed up the drain hole. Rain and snow filled the stern engine area up to the block. For several months. He drained it a year ago. I bought it last week. Charged up the battery. All I get is click. So I'm hoping to install a 91 Chevy fill size truck 4.3 v6 in its place. I read a bit online and on this forum about this kind of swap with little feedback on how things turned out for other boaters that completed this kind of swap. So I'm asking for input from anyone willing to guide me through this. I read that I must install marine head gaskets course re use the marine pulleys and accessories. What id like to know is what else should I be aware of if any thing else. Such as fly wheel swap etc.

 

I would think that your best bet is to strip the truck 4.3 down to the short block and give a good inspection. That is the time to do bearings, oil pump etc. Then reassemble with the marine parts. You could likely maintain the truck heads, possibly the cam. You'll have to compare the cam, and the heads to the components coming off of the marine engine. If I remember correctly your existing marine engine has a mechanical fuel pump mounted to the block. If the truck was efi, it would have an electric fuel pump. The cam on the truck motor could be different as it might not be designed to power a fuel pump. If it's raw water cooled, you definitely want to use marine head gaskets!

For compatibility & safety you are going to want to use any applicable "marine" parts over highway parts.

Good Luck!

 

Any input in crank flange bolt pattern? Thanks for replying. I really appreciate your input.

 

I can't say for sure, however I'd assume that it's the same. You should be able to transfer the marine flywheel and coupling over to the truck motor.

 

The 4.3 has had several changes in it's model run, many mimic the small block modifications, such as the single piece rear main seal, center bolt valve covers and hydraulic roller lifters. There are other notable differences, between the '87 and '91 versions of the 4.3, so only casting or block ID numbers can verify these differences. Post the ID numbers for both engines, which can be found on a boss, milled in the left side of the engine (when looking at it's water pump), just under the head to block joint, often under the alternator.

 

Glassport marine 4.3 v6 has # TC3266KB and the Chevy 1500 2wd I'll have to get from the salvage yard tomorrow and post the numbers.

 

Casting numbers would be helpful as well.

 

I couldn't read the block numbers, or casting numbers at the salvage yard today, that engine needs pulled yet. AC compressor was in the way to he its going to pull that motor next week