Hard starter in water...any ideas?

[whealy22]

Hey all. I just changed the wear rings and also the impellers. Went with stock wear rings and solas concord 14/22 impellers. The boat is a 97 speedster twin 85 hp 717cc engines.

Before the switch the right engine has always been a tough starter. Now after the switch it seems to be a little tougher now. I can get it to start up but i really have to crank on it and when i get it to start i actually need to give it gas in neutral to get it to stay running. After i do that though it stays running no problem. Any ideas?

Also after the switch i am getting about 6500 max rpms...is there anyway to get back to 7k again? I lost about 5 mph according to speedo:rant:

 

[whealy22]

I don't have a compression tool set so i can't be sure on that, the plugs were just changed and when i run the boat on the hose i don't see any leaks? Could it still be compression if i rev the boat up after it starts to get it running and then it stays running?


As far as the impellers go. I e-mailed solas and asked what they would recommend for more tourque on my boat and they replied 14/22 and a bunch of different shops also recommended that impeller. So that's why i went with it. I didn't seem to get to many responses on here on what pitch would be correct so i went with the most recommended.

 

[kustomkarl]

Before you do any modifications, you should always do a compression test, to be sure the engine is in top shape. The extra load on the engine with low compression is gonna be hard to start in the water. On the trailer there isn't any load on the impeller, so it will start fairly easy. Here is some information to doing a compression test;
You'll need a compression tester. Go to Auto Zone. I think they sell for like $25.00. The compression gage, will screw in the cylinder head in place of the spark plugs. To test compression, remove both spark plugs. Place spark plug caps on the plug cap studs near the cylinder head to ground the empty caps. This completes the circuit of the ignition electrical system and prevents any electrical problems from the caps being un grounded. Using the correct adapter for the threaded end of the tester,( same length of the spark plug threads length)screw in the tester in one plug hole. Hold the throttle wide open. Push the start button. Watch the compression gauge, when it peaks out at the most compression, let go the start button. Read the psi number. I would do it 3 times to be sure it is accurate. Check both cylinders the same way. The ideal compression is 150 psi per cylinder. If it is less, it's not a problem as long as they are close to being the same. If the psi is less than 90 it might need be time for a tear down and a rebuild. If the psi in 1 cylinder is say 140 psi and the other is 80 psi you need to tear down and repair. This difference is a lot then there is a problem. I hope this helps you.

Karl

 

[whealy22]

Ok guys! I went out to AutoZone and picked up the compression tester. You were right kustomkarl. $25.00 dollars. Do not buy the more expensive one the $25.00 dollar set works great. FYI.

So I went on the check the compression. On the hard starting motor I got a reading of 140 for one cylinder which I re-checked 3 times and then again so 140 it kept reading. On the other cylinder I got a reading of 130 psi. So a 10psi difference. I think I read somewhere that's safe? Or could that be my problem? I then went on to the other engine (which has no starting problems, knock on wood) and both cylinders were reading exactly 130 psi...which of course I made sure to re-check time and time again.

I then also hooked each motor up to the hose one more time to recheck for any visible leaks and noticed nothing at all. I also changed the spark plugs since I was right in there anyway.

I did notice 2 things. When I took off the spark plug wires on all 4 of the plugs there was some sort of silt/gunk black stuff. Is that normal?

I also noticed after I ran the engines smoke came out of the cylinder after I pulled the plug...which of course this was the engine NOT in question...and that is the engine I do get most of the smoke out of...so I assume this is normal?

Anyway...anyone have any ideas? I'm fresh out?

Possibly a leaky gasket as suggested by steveclv? I didn't see anything but I could be missing it.

 

[whealy22]

Thanks for the reply. I will do the WD40 and a little reving up tomorrow and see if that helps show me the lightttt! haha

Hopefully it will be a gasket. How long can i keep running it like this? Will a leaky gasket, assuming that's my issue be fatal to my engine? Or can i keep running it until i get some money together?

I will reply back with what i found out tomorrow. thanks for any info on my problem everyone!