Boat Vs. Car Parts?

[xienaeristarcraft]

Hello TeamTalk,

Would you please share your thoughts on using AC Delco or other car parts (E.g., distributor, rotors, plug wires) vs. ordering marine parts? Some of the prices on inboardgarage.com are more, but not that much more for the marine parts. Just wondering and I apologize if this has been discussed by my search for car did not yield any results.

[waterlogged882]

Originally Posted by xienaeristarcraft

Hello TeamTalk,

Would you please share your thoughts on using AC Delco or other car parts (E.g., distributor, rotors, plug wires) vs. ordering marine parts? Some of the prices on inboardgarage.com are more, but not that much more for the marine parts. Just wondering and I apologize if this has been discussed by my search for car did not yield any results.

Under the marine engine cover is considered a confined space, where potential gasoline fumes can accumulate. Any spark-related component must be arrested (spark encapsulated) to prevent the open source spark in the event of a build-up of gasoline fumes (highly combustible) under the engine cover.

An automotive engine compartment is not a confined space under the hood, thus less opportunity for accumulation of gasoline fumes.

Realizing your engine is not carbureted but since you asked; the engine carburetor also has to be marine compliant with a (low) pressure rated fuel line between the pump and the carburetor fuel intake, as well as have J-tubes and an overflow line in the event of a fuel pump malfunction. Also a spark arrestor (not an air filter) is required on top of the throat of the carburetor body in case of a back fire.

The fuel cell compartment is the same...a confined space...thus the blower in said compartment. A blower under the engine cover is no guarantee of adequate ventilation to prevent a possible explosion.

My adamant recommendation is to never use non-marine application where required by law (and safety of your family and friends) over a few dollars. Read that again.

Plug wires are spark contained by the boots.
Distributor (rotor and points) is contained by the cap. Electronics ignition distribution along the same lines.
Alternator is marine specific (VS auto).
Rotor is inside the distributor cap thus contained for spark between the contacts.
Starter is marine specific (VS auto) where the starter solenoid and brushes are contained within the starter.
Coil is self-contained.
Starter relay is self-contained. The relay and solenoid are two different components, often one confused or identified as the other.

Also the rubber caps and/or covers on all of the hot leads under the engine cover are spark-retardant and protected from an accidental cross of another wire or a loosely connected termination that could create a spark.

Biggest, first-thoughts are the alternator and starter, both marine specific.

This is for carbureted engines and a later model engine may have similar or other considerations as well.

Hope this helps and I hope I got it correct.

.

[Thrall]

You can use automotive tune up parts.
Caveat, marine spark plugs are stainless steel. Important if your boat engine is exposed to constant moisture. (Sits in the water or on a lift).
I’ve used regular spark plugs but my boat is a garage queen.

[Tsumi]

Circulation pumps are also marine specific. They have a bearing designed for use in water instead of coolant, and the pump impeller is made of brass? rather than regular steel.

[xienaeristarcraft]

These are great answers and I do appreciate the thoughtfulness. I am planning a tune up and obtaining a few spare parts (i.e., ignition coil) and I saw a mix of TT members using marine vs. automotive ac delco cross referenced numbers for ignition systems. I am going to stick with the standard MR43LTS spark plugs gapped at .045”; tightened to 11 foot lbs of torque. I will probably get the cap and rotor at inboardgarage.com. However, I was thinking about the ACDelco D503A Professional Ignition Coil as a backup (mine is working fine but never hurts to have a spare).

Alternator, starter, anything read or controlled by the ECU I would want to make sure are factory marine replacements (lucky I do not need these currently). I have had some bad luck with automotive aftermarket parts frying automotive computers.

[waterlogged882]

Originally Posted by xienaeristarcraft

These are great answers and I do appreciate the thoughtfulness. I am planning a tune up and obtaining a few spare parts (i.e., ignition coil) and I saw a mix of TT members using marine vs. automotive ac delco cross referenced numbers for ignition systems. I am going to stick with the standard MR43LTS spark plugs gapped at .045”; tightened to 11 foot lbs of torque. I will probably get the cap and rotor at inboardgarage.com. However, I was thinking about the ACDelco D503A Professional Ignition Coil as a backup (mine is working fine but never hurts to have a spare).

Alternator, starter, anything read or controlled by the ECU I would want to make sure are factory marine replacements (lucky I do not need these currently). I have had some bad luck with automotive aftermarket parts frying automotive computers.

Ignition coil, cap and rotor are OK for tune-up from auto store if that be your choice. The point is, an open source spark is not recommended for confined space use.

.

[93Prostar190]

These are all great points (see what I did there for you guys with older engines

Sometimes it is only the price difference. I agree with everyone above although some of the spark plugs I have used have not felt marine specific following the specs from Indmar (my 5.7 275 HP in my 95 for instance, seems like any ol AC Delco plug).

Starter, Alternator, and Water Pump should be marine for certain ... so should any boot around a 12V connector.

[88 PS190]

Originally Posted by waterlogged882

Ignition coil, cap and rotor are OK for tune-up from auto store if that be your choice. The point is, an open source spark is not recommended for confined space use.

.

I would probably not say that about the cap - side by side the marine ones seem better sealed on the SBC - the ford maybe similar.

[Mark rsa2au]

Originally Posted by Tsumi

Circulation pumps are also marine specific. They have a bearing designed for use in water instead of coolant, and the pump impeller is made of brass? rather than regular steel.

Interesting view held by many. Most automotive cooling systems using coolant also contain about 50% water and as far as I knew there is no lubrication provided by the coolant, only corrosion prevention and enabling the temp to rise about waters normal boiling point. I also assumed the Bearing was a sealed unit, which is why when it leaks the bearing dies - don't quote me here...

I replaced my circulation pump with a standard automotive unit a few seasons ago and no issues so far. When I researched the difference I found that only the backing plate was stainless vs zink coated and as I never boat in saltwater it became irrelevant. Comparing the pump that came off the boat after 20 years the impeller was not brass or stainless, only the backing plate. Then the price difference was AU$300 vs $80 so it became a no brainer - I could replace the Automotive pump 3 times with a 6 pack for each changeover and still be ahead.

Like others I will only use Marine Grade parts for spark control or safety-critical areas like fuel supply.

[Dredgeking]

Safety first. Use marine specific items. Back when I raced offshore, we would sometimes buy high performance auto starters and alternators and have them rebuilt into marine compliant parts. We could get better parts at a lower price.