1979 Johnson 85 HP V4 Seahorse Won't Start

[chadbrew]

Hi. Have been trying to get motor started forever with no success. Had it in boat shop and they said "Come take it back" can't figure it out either.
Compression test is good. Rebuilt both carbs with new kits. Cleaned them out at least 4 times thinking I missed something. Floats appear set right. New hose and bulb. New gas.
New plugs. Checked spark and appears to have good spark. Have tried to squirt gas into carb right before starting and still doesn't even try. Squirt a little gas into cylinders through plug holes and it attempted to start. Was my dad's boat and he passed 7 years ago. Only had it on water once and it wouldn't idle. Drives me nuts that I can't start it. Help.

 

[racerone]

Check flywheel key.--------Check for spark that will jump a gap of 3/8" or more with the plugs all installed !!-------Check / load test the battery.--------Take starter apart for inspection.----Note I did not say buy a new starter here.-----Some simple testing trouble shooting is required here.

 

[emdsapmgr]

Good suggestions. As you crank the engine, are the plug wet after cranking, or dry?

 

[chadbrew]

Thank you so much for your help. I checked the flywheel key and its right on the money. I took the starter apart (the springs were lots of fun) and cleaned it all up. It turns over much faster now. Cleaned all the connections real good. I'm not sure about the distance of the spark. I took each plug out and held it next to ground while turning the engine over and saw what I think is a good spark on all of them. Not sure if plugs are wet. I think I'll pay attention to that next time. Took gas hose off on engine side of pump to make sure gas is pumping. It sure seems like it would give some indication that combustion is taking place. When I put a little gas in the spark plug holes it kicks over like it would like to start.

 

[boobie]

Will the spark jump a 7/16 " open air gap when cranking on an open $8.00 air gap spark tester ??

 

[tblshur]

chadbrew my 83 v-4 will never start unless the primer is used and working, you probably already know that good luck:joyous:

 

[scrapper042000]

orange spark=weak ....blue = good spark ....make sure throttle is opening far enough ...raise up warm lever (way up) the 2 ive had would never start otherwise ...choke it until starts don't let off choke til then ............probably have the hood off when raising the warm up lever being the age it is (darn cables )and watch the throttle lever move .........maybe even have to help it carefully by hand before starting

 

[scrapper042000]

79 should have regular good old fashioned choke plates pop the front if she wont start ......make sure there closing completely ......85s are fussy

 

[emdsapmgr]

Once I overhauled my 79-it is really touchy as far as the choke goes. I just barely touch the choke and it's started. Floods very easily.

 

[chadbrew]

Well, I went out and bought my own compression tester and here are the results:
90
80
95
90
Seems low but I don't know. I choked the engine making sure they closed completely (in hopes of drawing some gas into the motor) and gave it full throttle and the old girl started. Wow, what a finicky motor. Thank you all for your help!! I'm still a bit worried about the compression, even though it runs now.

 

[racerone]

There are 4 small covers on the sides of the engine.---6 screws each and a $ 2 gasket.--Remove them and inspect pistons and rings.

 

[chadbrew]

Are the compression numbers bad? Seems like if 3 of the 4 are around 90-95, then that would be a normal reading unless the engine is just wearing out evenly across those 3 cylinders. But websites all talk about numbers over 100.

 

[chadbrew]

It is a model number 85TL79R, for what that's worth.

 

[chadbrew]

Never mind. Dummy. I'm suppose to take all the plugs out before testing. Not one at a time. All read between 115 and 120 now.

 

[durban]

At members on here have good knowledge as a team they will get it started for you i would start with check & see if the timing is within specks as per manual i think it 4-6 degrees then make sure synchronization is correct with butterfly's closed

 

[Bosunsmate]

ground all the plug wires then turn the starter on for 4seconds, remove the plugs, check they are all wet with fuel.
Light the wetness to check it isnt water.
This test is a must do on these motors when i work on my mates one

 

[boobie]

Read post # 5 again. Also it wouldn't hurt to do a good decarb on it.

 

[emdsapmgr]

Your engine should run ok with those compression numbers. My overhauled stock 79 85 hp runs 125 on all 4 holes. Wet plugs indicate that the combustion chambers are getting fuel. If so, and it has spark, it should fire. Engines with a weak ignition system may fire the plugs when held to the block, but may not fire them when under compression. That spark-gap test is a really good test of the ign system. (post #5, again..)

 

[chadbrew]

Thank you all so much. It finally started. I think it is just real touchy with choke and throttle. Now I'm back to the problem I've had from beginning. Sorta sputters when idling. The one time I had it in the water years ago it did this and wouldn't run under load at low speeds. Barely got it back on the trailer because of cross wind, drifting, and dying. Ran super good at high speeds but low speed would die forward and reverse. I don't have a manual to try and sync carbs or adjust timing. Lack of $$ has kept me from ordering one, hoping I could use the internet to find the info but no luck on that yet. Thanks again to all for your help.