Mercruiser 170 unable to start

[stacymd]

Hi,<br />I hope you people out there can help....I have an 85 wellcraft with 170 mercruiser..I had it out and was running fine for approx 1.0 hr...Was in idle for a few minutes when the engine stalled. I could not restart. It cranked but would not turnover. The batteries were fully charged before setting out. The crank seemed a bit weak like batteries were dying. ALso tried starting fluid.. Luckily, another boater towed me in. The next AM the boat started in my yard without even slightly cranking. Ran fine. I pulled the battery cables off the bateries to make sure that the system was charging and it appears that it was as the enigne did not die. ANY IDEAS??????

 

[Bob_VT]

Re: Mercruiser 170 unable to start

Fuel filter! That tiny minute filter that is inside your carburator.<br /><br />The dumb filter is no larger than a dime in diameter and about 1" long. If it clogged it will kill the motor and when the motor is stopped the debris finally settles in the filter allowing fuel to pass through again.<br /><br />I would check the fuel system and your points in the distributor cap too. <br /><br />Just a suggestion.<br /><br />Bob (I have the same year/type motor)

 

[beckerdg]

Re: Mercruiser 170 unable to start

I would also start at fuel filter. I have an 86 mcm170 and there is one at the carb where the main fuel line comes in, and one at the fuel pump on the side of the engine. If they look full of dirt that was probably it. <br /><br />I would go ahead and change points and condensor and retime at the same time. I had a similar problem where my engine ran great for 45 minutes then would start to miss badly. Next day would run great for the same time. Turned out to be something with the ignition. I would have saved myself a couple test drive trips if I would have changed the points/condensor with the fuel filters.

 

[stacymd]

Re: Mercruiser 170 unable to start

Thanks much for the advice all. THe points are new and boat was timed. The engine never sputters or misses. I was checking the web out and another boater had a similar problem also and it turned out to be the battery cable would heat up and cause hard starting due to not enough voltage to engine. I will change the condenser and check the fuel filters and take her out next week and hope it odes not stall....If you have any other ideas I would appreciate it..Thanks much.....

 

[Bob_VT]

Re: Mercruiser 170 unable to start

Probably the best suggestion which we all failed to mention is to get the manual!!! Even if it helps with one simple proceedure/repair it pays for itself.<br /><br />Bob