89 70hp Too much compresion?

[MTboatguy]

Hate to say it,, with the new batt and starter, but it still sounds like you have a bad electrical connection somewhere, if you can turn it by hand with the plugs in, you do not have to much compression, but if the starter will at least turn the motor, even if it is one revolution every 3-4 seconds, then there is a very heavy draw in that system, it might be a bad ground, or heavy corrosion on a wire somewhere. It does not sound mechanical based on what you are describing.

 

[Magnumu]

Have not noticed blowback, but I think exhaust may be partially blocked as well. Trying to figure out how to disconnect shift linkage to take bottom off. Looks like connector is behind vro and we can't get to it?

 

[racerone]

You need to answer question to get results and find a path forward.---- Use booster cables directly to the starter and does the motor turn over properly then ?----To remove the lower unit there is a hitch pin on the starboard side.---Then push the shift shaft to the port side and rotate that shaft.---That releases the shift rod.

 

[Chinewalker]

Blocked exhaust will not affect rate of spin. Only way you can have too much compression is if the cylinders are full of fuel. Being that you've spun it over with the plugs out, that is unlikely.

Check all cables and connections. Something is not right on the electrical side of things.

 

[Magnumu]

How do we reMove vro unit to access shift connector so we can split lower leg?

 

[racerone]

You do not need to remove the VRO unit to remove the lower unit !!!---See post # 23 for how to do it.

 

[Bosunsmate]

Are you trying to start on muffs or in a barrel?
Muffs means no back pressure nor the prop turning in water

 

[Tim Frank]

Double check the grounding

 

[laurentide]

Blocked exhaust will not affect rate of spin. Only way you can have too much compression is if the cylinders are full of fuel. Being that you've spun it over with the plugs out, that is unlikely.

Check all cables and connections. Something is not right on the electrical side of things.

Or water. These 3 cylinders can have a warped inner exhaust manifold plate that will allow water into the crank which will give you the symptoms that the poster has. But that water would shoot out of the lower plug hole when the plug is removed and engine cranked. Is there water spraying out?

 

[racerone]

????---Does this particular engine have an inner exhaust plate ??????

 

[Magnumu]

Sorry about delayed response, cell tower at home is down, I have to leave to check email or web. I will disconnect battery and wire from starter to solenoid and try jumping starter with nothing else connected. I believe this would isolate whether we have a wiring issue. Will probably be morning before I check in again. Thanks for all the suggestions/help

 

[Bosunsmate]

Sorry about delayed response, cell tower at home is down, I have to leave to check email or web. I will disconnect battery and wire from starter to solenoid and try jumping starter with nothing else connected. I believe this would isolate whether we have a wiring issue. Will probably be morning before I check in again. Thanks for all the suggestions/help

Are you on muffs or in a barrel?

 

[Bosunsmate]

????---Does this particular engine have an inner exhaust plate ??????

The answer to your question Mister is no

 

[Magnumu]

Jumping to starter with all other wires disconnected ended in same result, will not turn over with plugs in.

 

[Bosunsmate]

Jumping to starter with all other wires disconnected ended in same result, will not turn over with plugs in.

Ive heard about this once a long time ago :gossip:, the short of it is your motors toast, sell it for scrap, adios

 

[Fed]

Could the bendix clutch be slipping badly?
ie, starter spinning properly but not many rpm at the gear itself.

 

[laurentide]

????---Does this particular engine have an inner exhaust plate ??????

The answer to your question Mister is no

Sorry guys, earlier 80's model owner here :facepalm:. Don't let my ignorance detract from the actual good answers here, OP.

 

[Magnumu]

No water in motor, using muffs or currently nothing as just trying to get it to turn over, no water in crankcase. Starter motor not slipping, only stopping. Hopefully take lower end off tomorrow night to check for obstructions in exhaust.

 

[BigB9000]

I tried using jumper cables to starter once, had the same problem you are having.
Then I correctly connected the cables to the battery, and all was solved.

My guess is your cables aren't connected properly/tightly.
2nd guess is that your failed attempts have run your battery down.
3rd thought - your cables have rotted from the inside.

I have a 1-2 amp battery charger/maintainer, the $20 Black and Decker one.
Throw it on a low battery over night and in the morning you'll have one strong battery.

 

[Bosunsmate]

Sorry guys, earlier 80's model owner here :facepalm:. Don't let my ignorance detract from the actual good answers here, OP.

We all a so far