Non starting OMC 4cylinder

[C. B. H.]

Picked up a 18ft MFG boat w/GM OMC can you give me timing specs. firing order and plug gap . I have spark to plugs ,however motor will not start , has good compression also . Boat has sat for over 10 yrs have replaced oil , plugs and plug wires .

 

[tommays]

Re: Non starting OMC 4cylinder

gr<br /><br />if it sat for 10 years you have a fuel problem i dought it will run with out a carb rebuild and how old is the fuel in the tank ?? 10 year old gas is never happy<br /><br />tommays

 

[C. B. H.]

Re: Non starting OMC 4cylinder

No fuel in tanks I am using clean fuel freshly purchased

 

[vipzach]

Re: Non starting OMC 4cylinder

I tommays is on the right track about the card problem, if you have fire you need fuel, try spraying the card with berryman's card cleaner, but I bet you need a rebuild kit for the carb

 

[John Smith]

Re: Non starting OMC 4cylinder

First make sure you have good strong spark to the spark plug, you did not change any timing, or rotate the distributor. Second squid a small amount 1/2 oz of Gas at the time (use a small bottle) or use starting fluid into the Carb vent, try to start the engine, you may need to try several time if it turn over for several sec. it a good sign. Now check the linkage to carb, look into the open of carb if you press that linkage is there gas squid into the carb, if not check the gas line and filter to the carb if there is gas, if gas is there, you need to have your carb rebuild, I don't know how much do you know about car repair, if little take it to a carb place have it rebuild. If this boat had sit more that 1 year most of time it will gum up the carb, you need to take the carb apart and soap the carb with cab clean solut and install new carb kid. Be sure you have a repair manual. There is a lot more but just try this right now <br />2-16-05

 

[tommays]

Re: Non starting OMC 4cylinder

gr<br /><br />DONT use starting fluid it really tears up the motor and belongs on the list of what were they thinking<br /><br />if you have good comp,spark and fuel it will start<br /><br />my lawnmower cant even sit 10 months and run with out a carb cleaning let alone 10 years<br /><br />tommays

 

[John Smith]

Re: Non starting OMC 4cylinder

Gr,<br /> you need to post year, engine size, point/elec ign and any modif to the engine in order for any person to help you!!

 

[C. B. H.]

Re: Non starting OMC 4cylinder

tommays 1st off like you I would never use starting fluid . carb was drained and so was fuel tanks .I know the carb might still gum up ,but I am spraying gas in carb so I should still get some fire right ? I do have good spark at plugs as I checked each plug attached to it's own wire . other than it is a four cylinder and has points I am not sure of size or year other than pre 90 . on manifold there is a no. 1-22-88 could that be the year ? carb is a 2 jet rochester . <br />J.S. right now this is all I know for size and year

 

[Don S]

Re: Non starting OMC 4cylinder

If you are going to work on your engine and drive, get a service manual. You can't do the work if you don't know what the specs are.<br /> Order Service Manual here <br /><br />Here is some of the tuneup info.<br />Sparkplugs AC MR43T gap at .035<br />Timing 1° ATDC w/86 octane fuel, 4° ATDC w/89 octane fuel<br />Idle 500-600 rpm in the water in gear.<br />WOT 4200 to 4600 rpm.<br />Point gap .019 Dwell 32-34°<br />Firing order 1-3-4-2 distributor turns clockwise.

 

[C. B. H.]

Re: Non starting OMC 4cylinder

Don thanks for the specs. Have planned on getting Manual just wanted to get her to fire off and running Thanks again ,

 

[Mahoney]

Re: Non starting OMC 4cylinder

I had a huge problem starting a boat that had been sitting for 5 years myself. After Carb rebuild and new plugs, I was still having problems. First one, duh..was timing was 180 deg off. Make SURE your #1 is on TDC of compression stroke by plugging up the plug hole with your finger while you manually turn over the engine. I replaced points and engine got better, but it didnt really improve until I converted to electronic ignition. There are just too many things that can get off with points and condensors to hassle with it.

 

[Mahoney]

Re: Non starting OMC 4cylinder

Sorry about the huge pic, I was screwing around with profile and forgot. Ugg