won't rev up or plain out (long)

[lagoon bandit]

I have an early 70’s Chrysler outboard I do not have the original serial and model # however I have been using the serial # of 451HH to order parts and they have always fit. It is 45 hp 2 cylinders with a magneto spark system. I have replaced the points, condenser, fuel pump diaphragm, a carb kit, and spark plugs. Also I have been running it without a thermostat (I did not know)<br /><br />This is my problem the motor Always ran for about a year then out of no were it would not rev up or get up to speed. It would cut in and out. Sometime you nail it and it works fine the next time it back to not speeding up you could throttle in and out and mess with the chock and sometime it would run right. It revs up in neutral and out of the water. So then I began replacing part First I thought it was a wire short with the key so I put my own key and kill switch. Then I thought well it’s a fuel problem. So then I put new lines, primer bulb, fuel pump diaphragm, cleaned and installed a carb kit and of course new gas. The motor ran fine for a trip or two and there I was in the same spot<br /><br />So the I figured it was a spark thing so I put in new points and condensers I still have the old 70’s coils in it ($300 for new ones) to set the timing I just gaped the points at .020 (when the hump of the cam open the points that when I gaped) the I turn the fly wheel till the line on the flywheel lined up with the middle timing mark on the gauge then the adjust the spark control rod till the 1 point barley opened.<br /><br />After all that the boat ran good for 5 trips the one morning I forgot to put the plug in. I used the bilge to pump most of it out then I figured that I would plain out and pull the plugs so the water would get sucked out. But the boat would not plain out but I figured it was from too much weight from the water. So the next trip it would not rev or speed up but it started every time and doses not sound rough at low throttle. So the next trip I knew it was not going to run well so I stayed close to the ramp. I tried to plain out and could not so I spayed some mixed gas in the card with a spay bottle and nothing. Then I was drifting a spot I know on the ICW. I leave it in neutral so I can move out of the way of other boats. Then the motor stalls and will not restart. It always starts??? <br /><br />So last night the bottom legs of the motor was covered in black nastiness. It is the normal un-burnt run-off multiplied by 100. I have never seen it that bad.<br />Also the plugs were wet and I tested the spark and it is a nice blue spark that can jump over a ½ inch. After I tested the spark I put the plugs in hit the key and it started first try<br /><br />Okay that’s the whole story I can not figure this out I work on cars and trucks all the time why can’t I get this outboard to work right Also I have both repair manuals and they do not help me much<br />Thanks for the help in advanced<br />-Richard<br />aka lagoon bandit

 

[byacey]

Re: won't rev up or plain out (long)

I would try replacing the plug wires, these move with the armature plate and are always flexing; being as old as they are the insulation may be breaking down. The other thing to check is the fuel filter,pump,carb float bowl and jets. Make sure they are spotless. I would try the wires first.

 

[eurolarva]

Re: won't rev up or plain out (long)

Have you done a compression test? Testers run about 30 bucks from Sears and can be used on all equipment that uses a spark plug. Have you looked at the tips of the spark plugs? Is one dirty and the other clean? Running without a Tstat will run a rich condition, however will not give you the grief you are seeing. I would start with the compression test then you will have to look into the electrical system. Could be a coil crapping out or the magneto itself. The marine doctor has a magneto test procedure at this LINK Maybe post this thread on his site and see what he says. I can guarentee you though he will want to know them compression numbers first.<br /><br />Good Luck

 

[steelespike]

Re: won't rev up or plain out (long)

It sure sounds like you are losing spark on one cylinder.Have you tested for spark when it won't perform?Be sure all wiring is sound.Sometimes plug wires will rub a spot in the insulation that will only cause trouble in certain positions.That extra sludge would seem to indicate no spark on at least one cylinder.Unfortunately it may be time for at least one coil.You can switch the coils around to see if the problem follows.<br /> Years ago I changed just the coil from an OMC armature and put it on a Merc armature.It worked but my problem was a bad magnet in the flywheel.<br /> But maybe you could try something like that for your motor.I think OMC coils are about $30.<br />You may want to put in new plug wires.<br /> NAPA auto parts lists marine plug wires in their 600 page marine products catalog.18-5228 9" wires.Unfortunately some branches don't know about the catalog.

 

[lagoon bandit]

Re: won't rev up or plain out (long)

I did a compression test when I first got the boat and then again when it started to mess up the manuel say 115-130 I was running 100 or 105 in both I will do one now and see what I get<br /><br />The wires are part of the coil I need a new coil for new wires the coils do not have crack<br /> <br />not having spark in one cylinder is a great discription<br /><br />the wires look good but you know how that goes and when it runs good both plugs look good and when it is messing up both plugs are wet and fouled<br />As far as testing for spark when it is messed up it always runs so it has spark but when it would not start yesterday I could not test it till i got home I had spark the put the plugs in and it started fine

 

[eurolarva]

Re: won't rev up or plain out (long)

From your description of the spark plugs I would agree that the head gasket is not bad. When you test the compresssion test it with the motor warm. Then squirt some two cycle oil in both cylinders and re test compression. See if the numbers improve. Also what kind of spark plugs are you using? The original factory plugs no longer exist. I find the L82C work the best on my 45.

 

[byacey]

Re: won't rev up or plain out (long)

A visual inspection of the wires won't reveal much. At 10,000V + all it takes is a little tiny pinhole for the voltage to bleed off to ground. If you can get your motor started at night you may see the leakage on the plug wires if it's very dark. Caution!!!Don't try to put a blanket or something similar over your head and motor to block out the light - if the flywheel grabs it, your finished -literally.

 

[lagoon bandit]

Re: won't rev up or plain out (long)

I will be doing the comp. test tomorrow and I will try the oil trick also.<br /><br /> when I do the test how long should it hold the compression for?<br /><br />As far as spark plugs go I use 2 kinds I do not have the numbers with me I post them tomorrow<br />the ones came with the motor the guy told me "those are the plugs you want to run with the gas we have these days" and then I use what ever one the manuel say when I go to the parts store the crossrefrence the # from the manuel to a diffrent champion plugs<br /><br />I can say the one that came with the motor have longer threads<br /><br />Also I cant say for sure but I do not think my problem has changed with the diffrent plugs but it dose make sence if my plugs are not burning all the fuel that could lead to a problem<br /><br /> since the ones I have now are all fouled up I plan on buying some new ones I will buy the L82C<br /><br />Also I did froget to mention one thing that can have a major impact I had cracks in the coils when i first got it so instead of dropping $300 for new ones I put opoxy on them to seal the cracks with the crack the motor missed fired bad and the after I seal them the motor ran real nice when the coils were cracked at night you would see lots of blue sparks but now you can not see any blue<br />Tanks for the help everyone<br />_Richard

 

[byacey]

Re: won't rev up or plain out (long)

If the coils were cracked they have absorbed moisture into the windings. Unless you were to place them in a vacuum bell jar to remove the moisture, it's still there. The problem now is the moisture is sealed inside the coil when you put epoxy on the cracks,and you can still have internal arcing and current leakage. Best to try and source out some replacement coils because these will surely lead to continuing problems down the road. The spark plug heat range is important - too hot and you get pre-detonation, too cold and they foul up with deposits. best to use the ones specified for your engine, or an approved equivalent. I don't have the exact manual for your engine, but the older 45s used an J-4-J, I am sure there is a replacement for that plug available.

 

[byacey]

Re: won't rev up or plain out (long)

A quick update - I did a search for that plug, and a J-4-J is equivalent to a Bosch W5EC, an AC V40K or an NGK B8S.

 

[eurolarva]

Re: won't rev up or plain out (long)

J4J is only recommended for the series 2000 20 HP motor. Magnapower 2 calls for a UL18V which I believe is a gapless plug and newer model 78 and up are calling for a RL4J plug. All other 2 strokes call for L4J which was replaced by L82C Sounds like the coil is probably your problem. I would stick with the plugs you have in the motor now. If it was running good with them before they probably are the correct plugs. You might want to check with the Marine Doctor for correct plugs. He also might have the coils you need.

 

[lagoon bandit]

Re: won't rev up or plain out (long)

So I finanily ran a comp. test I had 95 psi on the top one and 98 psi or so on the bottom.<br />After that I tried to do the drop cylnder test and it would not run so after that my buddy told me to pull the exhaust cover and see if it is cloged up so I did<br />I will ammit that when I looked in there it was real gunked up but not cloged but I could see plain as day that my top piston had a 1/4" wide grove in it so proceded to pull the port cover and sure enough more groves and to top it off both piston have groves in them <br />so it looks like I found my problem <br /><br />So dose anyone have any ideas???<br /><br />Dose any one need some parts???

 

[eurolarva]

Re: won't rev up or plain out (long)

Sorry to hear the bad news. Compression test usually would have shown that especially if it is only one unit. Best bet is to part out the motor on ebay. Parts for that motor is tough to find and even if you could it would cost at least 1000 dollars to have the rebuild done. Get yourself something newer like a merc or an evinrude. Stay away from chryslers and force unless you get one for a really cheap price and you can test drive it.<br /><br />Good Luck.