Engine won't go past idle in gear on a cv-4 90* 1993 J115TLET

[Bama Hound]

Engine won't go past idle in gear on a cv-4 90* 1993 J115TLET
I have built carbs, replaced water pump impeller, replaced starter and solenoid thermostats and relief valves and regulator rectifier. I have timed WOT-4* which is 24 BTC I have set idle timing to 4* BTiC. It will start idle good (kind of) idles at 1100. Drop in forward and idles at 950 on trailer in the lake. If you try to advance throttle it will croak. I have had this boat 3 years but didn't run it last year cause health problems. The way I am reading things I should be able to pump bulb until firm. This has never been the case. I would pump it 10 or 12 times and if I went out within the next 3 days I wouldn't even bother to pump and it would start and run fine. I have a VRO changeover. Boat has built in tank. Hose and bulb are new. Anybody want to venture a guess here. I did a compression test on cold cylinders (because it wasn't running at the time) numbers were from 95 to 105 shot Marvel Mystery Oil out of squirt can in just prior to test. Have to admit here while setting WOT timing only tested spark on #1. Which I could hear but couldn't see in bright sun, I have to do timing at dusk even to be able to see timing light, and mosquitoes size of Hummingbirds are only helpers. I am kind of lost here and my "sea time" is drawing to a close. Live on a lake that drops 5ft.sea level starting Sept. 28, so any good guesses are more than welcome. P.S. redid link and sync after carb removal as well as WOT stop. I am remembering now that if I put boat on ramp and tried to power up to keep from drifting off it would die after a full power push is this normal or has it had some ongoing problem?

 

[Bama Hound]

Re: Engine won't go past idle in gear on a cv-4 90* 1993 J115TLET

I know you have got to know something, to be able to find out something. So I wanted to be able to give "good" numbers, so I went and warmed engine and pulled it out of water and checked compression. The numbers are as follows. #1 90*, #2 105*,#3 105,#4 90*. While those numbers are not really stunning it ought to be able to pull a greased string out of an elephants patootie which it won't. I found one stupid blunder I pulled. When I was checking plug fire I checked 2,3,4 to be able to jump 7/16' gap. I put gap checker on #1 and had my timing light on the wire but I never checked the jump as timing light was blinking. I have to be on step ladder to check timing so I neglected to check actual gap. #1 will only jump 1/4" gap and not too strong. I hope a coil will fix this. Is that right? I know I had 1 plug wire off one time and I would die when put in gear. :facepalm:I am going to swap coils and see if weak spark follows swap. Fuel bulb will get firm if engine is running, but not if not running. Is that of any significance?

 

[Joe Reeves]

Re: Engine won't go past idle in gear on a cv-4 90* 1993 J115TLET

The spark test should be done with all of the spark plugs removed in order to obtain the highest cranking rpm. THe engine must obtain approximately 300 rpm in order to engage the ignition properly for that spark test. Having even one spark plug installed is going to slow it down!

If possible, running on a flushette with the water turned on full blast and engine running at idle....... One at a time, with insulated pliers, pull the spark plug wire off of a cylinder... put it back on... go to the next spark plug and repeat until you've been to all of the spark plugs. If the spark exists, you'll be able to hear it over the roar of the engine when you hold it close to the plug.

You should have the same response, the same rpm drop on all cylinders when you pull the related spark plug wire. Do you? Do you have spark on all cylinders?

If you do not have spark on all cylinders, then obviously a ignition problem exists... BUT if you do have spark on all cylinders and when doing the "pull the spark plug wire test", you have a cylinder or cylinders that give no response, no drop in rpms, that would lead me into the fuel system (carburetors).

The brass high speed jets are located in the bottom center portion of the float chambers and fuel must flow freely thru them before it can gain entrance to any other fuel passageway. It's best to clean them manually and carefully with a piece of single strand steel wire as carburetor cleaner just doesn't do that job properly... this would be worth double checking.

One clogged high speed jet...... the engine will fall on its face when throttle is applied.

Also... if the engine seems to lose a lot of power when put into gear, check the shift cutout switch. To do so, find the switch by following the shift linkage feom the cable to the engine. You'll come across a weird looking switch with two wires, one black, one black/yellow. Follow the black/yellow wire from that shift switch to its plug in connector and disconnect it which eliminates the shift switch function. If this test causes your problem to cease, then obviously the switch needs replacing.

Be sure to reconnect that black/yellow wire as it's function is to help you get the engine OUT of gear. With it disconnected, on various models, it is impossible to get the engine out of gear unless you shut the engine down.

 

[Bama Hound]

Re: Engine won't go past idle in gear on a cv-4 90* 1993 J115TLET

Sorry it took so long to get back. Foul weather and other considerations prevented more timely reply. I swapped my #1 & #3 coils and the weak spark followed the swap. I replaced the weak coil and did a trailer on throttle test and it would push good.

The problem went back to a bad thermostat on starboard side. Overheat weakened the #1 (top) coil. I tested the spark on #2, #3, & #4, using a spark gap tester. I put the gap tester on #1 and then had to climb a step ladder to be able to read timing marks. I never looked at the spark length on #1 as timing light was blinking.:redface: DUMB! When I pulled coil it looked cooked, but didn't appear so when mounted.

I am glad it didn't get to where I was pulling plug wires from a running engine. I quit that 30 years ago.I get lit up every time somewhere in the process. I got "hit" onetime with leather palmed work gloves on. It got me through cotton part of fingers, I guess. When I used pliers I would damage boot so I quit. I was told that it was bad on ignitions (on cars) so I started using putting old plug in wire and using pliers to ground plug to block. That being said I can see live test would show better results. I didn't have to have much excuse to quit.

I did do the compression check like the FAQ said. I mislead you probably. I sure feel dumb. The problem was staring at me and I was looking the other way. Thanks for your help maybe this confession will keep somebody else from pulling the same stunt.