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How the marine specific parts in do differ

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"For LM318 225 (-73):

"For LM318 225 (-73):
How the marine specific parts in do differ from e.g. the normal Chrysler parts?

E.g. what marine specific there are with plugs, head gaskets, cams, heads, distributor, cap, fuel pump, starter, alternator, voltage regulator, carb, etc. in detail?

What cams does the LM318 have?
Probably the head has some differences in the ports (marine has smaller ones, as Fastjeff pointed out earlier).

I do have some engine manuals but those do not open these in detail level ;-(

And if moving from 318 towards to 360, are the differences somewhat the same?"
 
"OK...
Plugs: marine engine

"OK...
Plugs: marine engine usually have a particular "heat range".. do not substitute.
Head Gaskets: may of may not be different, but overall usually are...do not substitute
Cams: usually different, optimized for operation in a boat. You can substitute if you don't care about performance.
Heads: Often the same, but somtimes not. See comment above.
Distributor and cap: Marine specific for safety reasons.
Fuel pump: Marine specific on some engines. If the part nymber differsbetween automotive and marine, stick with marine.
Starter, Alternator, Voltage Regulator: see comment about distributor.
Carb: see above.

318 vs. 360... Differences apply to all marine engines.

Putting non marine parts on a marine engine can result in safety issues, the Coast Guard citing you for violations if they ever stop you for a safety inspection AND... if you ever do have an insurance claim, you probably won't collect a dime. If anyone gets hurt you better have deep pockets."
 
"Arto. You would have worked h

"Arto. You would have worked hard your whole life. Maybe have a family and grandchildren. I know what my life is worth. Have a think what your life and those around is worth!! You carry PFD's and fire extinguishers. Good! You may, get a chance to use them! If you are lucky. Robert is correct. The life lost, may not only be your own. Coaster"
 
"In reference to Arto's qu

"In reference to Arto's question about marine parts, did I definitely make a mistake by changing my distributor to electronic ignition and getting the parts from a Chrysler dealer.
For my 318 eng I bought "Mopar Performance Electronic Ignition Kit with Vacume Advance Distributor" part # P3690426, P3690427, & P3690428. That's distributor,coil and ECU. I haven't started the engine yet.
Thanks"
 
"I maybe wrong on this, but I&

"I maybe wrong on this, but I've never seen any marine engine with a vacuum advance! Usually just a centrifugal advance, and that advance system is optimized for the marine application.
There are ad-in kits that allow you to keep the existing distributor, cap, rotor and advance mechanism and still give you the benefits of electronic ignition while not violating the marine safety design parameters of the distributor."
 
Frank and Atro. As one who has

Frank and Atro. As one who has suffered gas [petrol] burns as a boy i can assure all it is not recommended. My suggestion is to raise correspondence directly with the manufactures and CC copies to your Coast Guard. The manufactures will then advise if suitable for use in a marine environment. I feel the assurance of Coast Guard review would generate a valid result. Frederick
 
"The distributor cap must be s

"The distributor cap must be sealed or screened to prevent ignition of gas vapors in the bilge. Automotive caps are not designed with this in mind. To prevent the use of an automotive cap, the original Prestolite marine distributor will not accept an automative cap. Only a marine cap will fit."
 
"Frank, I replaced my distribu

"Frank, I replaced my distributors with the same kind that you have about 10 years ago, never had an issue with any of part of the kits, even had a police inspection, passed with flying colours, the vacuum advance only comes into play if there is a vacuum line hooked up to it, I run Accel super stack coils, & opened the spark plug gap up to about 50 thou, ( RN9 Champions), engines start first turn of the keys, even after sitting for a week,
Pete."
 
FRANK LIPERE You won't eve

FRANK LIPERE You won't ever have a problem until you have some type of gas spill and have fumes and then you can KISS YOUR XXX GOOD BY Things happen fast enough in open water no need to make it worst by doing something stupid. PETER it almost sounds that you my be on barrowed time Hope not.
 
Hi. We had some stupidity over

Hi. We had some stupidity over here last night. Two xxx xx worker were responsible for an explosion at one of our many tunnel sites. Call up couriermail.com.au and search for "workers cigarette causes huge blast at tunnel worksite" . The right ratio of fuel vapour and stupidity. They did not have to swim! Frederick. PS I thought the topic would have been dead and buried by now. I hope it is only the topic which will have that result.
 
"This subject seems to have op

"This subject seems to have opinions.
Which is good.

The original idea behind this subject was to find the engine part differences between Marine and normal Chrysler parts.

As owning a rather old (-73) LM318 and seeing it's current oil consumption, the engine repair / buying remanufactured / swapping into 360 options are in my mind.

I was interested on the "marine cams" as they seem to be a bit of mystery as there are no details about their degree or lift.
The normal engine tuning offerings do target usually higher peak hp, than to high torque (even from low rpm).

The heads seems do have quite a lot of difference if considering their flow. (specially when moving from 318 to 360).

I agree that the electric parts do have always a bigger risk factor in marine environment. Bearing that in mind, it would be interesting to know that are there any newer parts in that area (e.g. when converting to electronic ignition, etc.) (this does not follow the mentioned Prestolite marine approach).

As living in Finland, here we do not have any such coast guard / police inspections with boats.
Thus my boat club requires an overall inspection every year (but that is rather high level one)."
 
"AS someone who narrowly misse

"AS someone who narrowly missed getting blow up with wife and family some years ago, I am quite sensitive to the matter ( The cork gasket on the fuel sender crumbled and leaked... filled up tank, put 1/2 inch gas into bilge of a 23 Ft ChrisCraft Lancer!)

While the USCG only performs a safety instpection when and if they happen to stop you on the water, I think I prefer Finland's approach. Here in NJ at least one boat a year has a "happening".

Handy hint to all with older boats. If your fuel sender's gasket is cork, replace it."
 
"That I can understand.

Btw

"That I can understand.

Btw. the local procedure that here is no such official safety inspections (like USCG) does not remove the responsibility from me. I rather think that it raises the need to be aware about any safety issues, cause when there is a problem (caused e.g. by my slippery safety actions), I'm the responsible.
The local boat clubs here do have few dedicated persons that inspect the members boats every year, but the inspections focus is related into overall boat safety and they do not open the possible problems e.g. with these older inboard engines, as it would be too much for a single inspector.

Thus, if considering that the -73 based Chrysler engine technology could have gained some improvements during the years and if being forced to do some major reparations to the engine, it would be interesting to know that what such options are available."
 
"Bunches of questions.......

"Bunches of questions.......

Both 318 and 360 heads have tiny little valves and ports (for improved mid-range torque). Standard, 318 and 360 automotive heads have much bigger exhaust ports and their valves are significantly larger--the intakes are about the same. (I have learned to use dinky 273 cube Mopar V-8 exhaust manifold gaskets or they leak.)

Marine head gaskets are stainless steel, but automotive gaskets are okay IF you use fresh water cooling.

The cams are very mild to improve mid-range torque.

The 318 motors use a different flywheel and damper (and maybe the oil pan as well--never been able to confirm that).

Power wise, there's little CRUISING difference between the 225 and 240 hp. 318s, or the 250 to 275 hp 360s. Only when running flat out (who the hell does that!) is there any real difference.

Hope that helps,

Jeff"
 
The only NEW Distributors to u

The only NEW Distributors to use in a marine app is the new Mallory units. Very good units and Marine certified. The factory Chrysler electronic's are not marine units and you put your family and friends at risk. If your distributors need to be replaced use the Mallory units. The best on the market in my opinion.
 
"Yes, the Mallory seems to hav

"Yes, the Mallory seems to have the word "Marine" in their web-page when looking their distributors.
Thus their prices are rather high...

What are the OEM cams in the marine 318 / 360 engines?

WOLVERINE offers e.g. like this:
CAM PART # CS4109 SPECS:
INTAKE LIFT .429
EXHAUST LIFT .444
DURATION AT .050
INTAKE 210 DEG.
EXHAUST 220 DEG."
 
Rather high? Not when you cons

Rather high? Not when you consider it is a all in one unit. and ANY TRUE marine item is more that a automotive counterpart. I don't know about you but my family and friends are worth the few extra $$$'s you night save on a component. If your using a automotive part make sure your life insurance is paid up.

Dave
 
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