2002 Mariner 60hp 4 stroke water pressure, priming and stalling

Hello all, i had some trouble with this engine last year and could not get to the bottom of it. I am not sure if the problems are all linked or individual. I noticed first that the tell tale was not peeing as strong as it had been previously close to the end of last season so i cleaned the water hoses inside the cowl with compressed air and removed any obvious salt build ups. This didn't seem to help much so i changed the impeller too but the old one looked fine and there is still not significant difference. Could this simply be a problem with my flushing attachment such as too high a pressure in the hose.

Second problem was more worrying, the engine would bog down/stall badly at times, sometimes after 20 mins other times at the end of the day. I have had the carburettor cleaned since then just in case its water or dirt but could this be a limiting from a lack of cooling water, there is no alarms on the engine as far as i know.

Thirdly, i cannot get the priming bulb to go hard at all, however the engine will start ok, it had always hardened up after a few pumps before end of last season so i changed fuel tank and fuel leads just in case there was air getting in but still the same problem. Any suggestions welcome as to what could be causing these problems. Ciar?n, Ireland.

Re: 2002 Mariner 60hp 4 stroke water pressure, priming and stalling

If you can't get the primer bulb to firm up the float level in the carb(s) is not set right and you are pumping fuel into the engine. Verify that the warning horn is working. The engine may be overheating and you don't know it. Perhaps a stuck thermostat and/or bypass (poppet) valve may also be a factor.

Re: 2002 Mariner 60hp 4 stroke water pressure, priming and stalling

I had a problem with the cooling on my 1998 50hp mariner 4 stroke:

http://rib.net/forum/showthread.php?t=35217

I replaced my impellor and checked the thermostat was workung before checking / changing this grommet.

the problem is you have to do the whole dissasembly to check to see if it is the grommet or not, and once the powerhead and mid section are off you MUST get new gaskets, and these are expensive ( Approx ?150 for 2 gaskets and new grommet )

Have you run it in a tank rather than on muffs to eliminate they are the problem?

Re: 2002 Mariner 60hp 4 stroke water pressure, priming and stalling

Thanks for the replies, i will test the thermostat as it hasn't been looked at yet, what temp should it pop at. Would the engine not be flooding itself if the fuel was entering the carb constantly when i am priming the bulb. I started the engine again today first time even without a solid prime. I don't like the sound of the disassembly for the grommet but very helpful to see that it could be a possible cause for this. It has a similar tell tale when started in a water tank as it does on muffs. I will look at thermostat and then think about the more costly grommet procedure Cheers.

Re: 2002 Mariner 60hp 4 stroke water pressure, priming and stalling

The manual for my 50hp says :

Thermostat valve opening temperiture 48 - 51 degrees C
Full open Temperiture 63 degrees C