tune up For Mercruiser 188/ ford 302

[holorinhal]

I want to do a complete tune up on My twin mercruisers.
Can I just go to the auto parts and buy distributer cap,points and condensor,rotor buton, coil, plugs and wires for an automobile ford 302 cid, or do I have to use special marine parts?

[jabroni]

While you should always use marine parts(these are always more expensive but are built for safety- they are sealed and won't spark igniting fumes or gas vapors in the engine bay. I have a Ford 302 in my cruiser which I just tuned up. I compared parts and found that they were identical. My mechanic said I should always buy marine parts, but said I should worry more if it was a relay, or alternator. Hope this helps

[PAR]

Most automotive parts will corrode pretty quickly in the marine environment. Marine parts are made with non-corrosive or corrosion resistant materials. Something as simple as an automotive distributor rotor, may use an aluminum or "pot metal" rivet to hold the contact spring to the plastic rotor body, which will corrode, causing it to fall off, probably dropping into the points and making a mess of them to say the least, if not getting past the breaker plate. Yes, automotive parts will fit and the engine will run, but you'll replace them more often and lets hope when they fail nothing else gets "taken out" with it.

[Frosty]

Just about everything on your list is the same as.

You dont get marine plugs or leads or distributor cap.

If you take the boat home with you where it can be washed and stored I would use what you want.

The whole engine is automotive.

[CDK]

There have been several similar discussions on this forum.

PAR is correct, at least in theory. But we live in a commercial world where sellers have understood that the same product with another label brings a triple profit. In other words: most of the time, you are cheated when you ask for marine parts.
Some examples:

Marine spark plugs corrode just as quickly as automotive ones because they are made from the same galvanized mild steel, but you pay for stainless.

Mercruiser uses marine alternators with a wire mesh filter and a cover at the front side to suggest an explosion proof construction, but the back is completely open.

The same company uses relays on the hydraulic pump that cost approx. 5 times more than automotive ones but are in fact inferior. They not only corrode but also employ a thermoplastic insulator which softens at moderate temperatures already and causes them to malfunction.

The keyword is common sense. Look at what you're buying, compare different brands, then decide if it's worth the extra money.

[jabroni]

I couldn't have said it better CDK. Nothing produced will ever stand the elements or test of time. Use your head, and service your boat regularly.

[gonzo]

Mercruiser alternators have flame arrestors on both sides, one screen is in the inside and can't be seen without taking them apart. Marine sparkpugs of better quality are stainless and won't seize on the heads. There are usually claims with numbers as "five times less" or whatever, but they have no basis in reality. Also, you are in the US where there are safety regulations and explosion protection is required by law.

[CDK]

Originally Posted by gonzo

Mercruiser alternators have flame arrestors on both sides, one screen is in the inside and can't be seen without taking them apart. Marine sparkpugs of better quality are stainless and won't seize on the heads. There are usually claims with numbers as "five times less" or whatever, but they have no basis in reality. Also, you are in the US where there are safety regulations and explosion protection is required by law.

Maybe they made an alternator especially for you Gonzo, but the ones I have seen and taken apart were cheap Motorola alternators with a screwed on flame arrester at the terminal side and 4 large holes behind the pulley. The last pair of Merc 3.0LX alternators did not have any flame arrester at all, but the terminal side was closed with a plastic cap, with openings on all sides between the stator and the covers. And they always come with marine spark plugs that already show corrosion when you lift the engine from its carton.

But it could very well be that products for the US are different from the export ones that do not need to comply with your regulations.

[fasteddy106]

Even though I change my tune up parts every year, I still use marine parts. If you shop smart and don't just wander into the marina parts store you can buy marine grade parts comparable in price to regular automotive parts. I've spent a lot of years dealing with auto parts and there is a difference between marine and automotive grade. The overall difference in price is not worth the risk of breakdown or fire.

I saw a guy with a constant cooling problem. He did the thermostat, hoses, cleaned the manifolds & risers, replaced the impeller on the outdrive then decided it was the head gaskets. When he removed the water pump the impeller on the inside of the pump had corroded away as it was an automotive pump. I asked him why he didn't check the flow or pump first he told me he didn't see the need as the pump was only a year old. He learned the expensive and the hard way the difference in construction of automotive vs. marine parts.

[Frosty]

If you have a closed cooling system, (i cant believe you would cool with raw water these days) you don't have any probs, the engine does'nt know its in a boat.

Marine alternator cores are insulated with something different from automotive, I forget now what it was.

[gonzo]

NAPA carries marine parts at cheaper prices than the marinas usually do.

[powerabout]

Originally Posted by Frosty

Just about everything on your list is the same as.

You dont get marine plugs or leads or distributor cap.

If you take the boat home with you where it can be washed and stored I would use what you want.

The whole engine is automotive.

and if his engine has the distributor made by Mercury....you ant gunna get that in a car shop.
( he got lucky with the dizzy as 888 233, 255's had about 4 different ones)

[powerabout]

dont forget to ask your insurance company if you can use automotive electrical and fuel system components....
Which is illegal in the US due to Coast Guard rules
Mallory and Accel etc make marine distributors..I wondor why

[Frosty]

Powerabout are you near Tuas, Jurong.

[powerabout]

No I live in Changi
but in the med at the moment.
cheers