View Full Version : Merc 57L GM parts compatibility

04-14-2006, 04:04 PM
"Does anyone know what model/year GM engine is compatible with a 1990 5.7 mercruiser? I'd like to be able to buy replacement parts at the local auto store (belts, filters etc)."

04-14-2006, 04:31 PM
"Any time you need to repalce a belt, take the old one in with you. If you have room to get at it, I recommend the AC PF-1218 filter. It's larger and has good anti-siphon characteristics. WIX and NAPA Gold are also highly rated. If you want to replace internal parts, look on the block and the heads for casting numbers. For Tuneup parts, there should be a sticker on the flame arrestor cover with the spark plugs, gap, oil types, etc. Yours is pre-vortec so it probably uses AC MR-43T spark plugs gapped at .035"."

04-14-2006, 08:59 PM
"You won't be able to match belts other than by length, I have yet to see a marine engine with a smog pump or an AC compressor on it. Same with tune up parts. Other than oil filter and spark plugs, not much else is going to work. Get friendly with your marine dealer. He's a good guy to know when you get in a pinch."

04-15-2006, 01:00 AM
"The tune up parts are all available at auto parts stores unless it's the Merc electronic ignition and in that case, you'll need to call aroundfor a car parts stores that has access to marine specific parts. The marine TBI motors use a regular GM style distributor with the IC module in the distributor."

04-17-2006, 10:55 PM
"As always, stay away from automotive strarters, alternators, distributors, fuel pumps, etc because of very real fire/explosion issue!


04-18-2006, 12:15 AM
"I think the fuel pump is mechanical and the car pump is fine. Even with the mid-'90s Mercruisers, the electric fuel pump is a Chrysler car part. The starters, alternators and distributors I definitely agree about, though. They need to comply with Coast Guard regs and cause no sparks."

04-18-2006, 12:27 AM
"Auto mechanical pump diaphram busts, gas leaks on ground. Unless it's on a boat, then it leaks into bilge.

Marine mechanical pump leaks, leaking fuel goes through hose into throat of carb. Runs rich, uses too much gas,smokes, DOES NOT BLOW UP!


04-18-2006, 09:33 AM
"Good point about the hose. Actually, most of the boats I have worked on have electric pumps."