Starting Problems

FishHunt23

Seaman
Joined
Jan 4, 2007
Messages
50
Just installed a new fuel pump on my 1988 70hp and installed a new gas line and tank fitting, and cleaned the fuel pick-up. Prior to this repair I had a hard time getting her started, and had to pump the bulb to keep it going once I did.

Took it out last night for a test run. It fired and ran right away. But like a typical older engine it stalled because I wasn't paying close enough attention to the primer and the RPMs. One it stalled I had a very hard time getting it re-started Even a shot of starting fluid didn't help. I was starting to wonder if I had lost spark. Checked that and it was fine. So I cranked the engine like crazy ... eventually, it fired and started. I let the engine warm up for a while and ran it. It ran perfectly! Smoother and quieter than it ever has. I shut the engine off with the key and restarted it right away without a problem. Took the boat out for a run, and things kept going smooth as silk. Got back to the landing and as I was driving on the motor stalled when I let the RPMs get a little low (need to adjust the idle speed, but not a big deal). Then I spent the next half hour trying everything I could think of to get it re-started. Nothing worked, and it was like the motor was dead. Crank and crank and crank ... no fire. I checked to make sure it was in neutral. I checked the kill switch. I checked for spark. Everything was fine but it wouldn't go. Because it was essentially the same problem I had when I first tried to start it I assume it is a problem that I need to fix. But because I essentially have a new fuel-delivery system from tank to carb, and once I got it going it ran very smoothly, I have no idea what to check for. I looked at the plugs and they seem fine. All of them have spark. The gas is new. I tried two different tanks of gas (built-in and spare) with different lines to make sure it was getting gas. Bulb in gas line stays firm after I pump it and, again, the engine ran great once I got it going.

Any ideas on what I should look for? I'd really appreciate any suggestions. This engine is driving me crazy. I had it re-built last year and it basically started/ran fine until the fuel pump went bad. Now I'm ready to use the damn thing! :)

Thanks for any help/advice.

John
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Starting Problems

what did the plugs look like, black and dry, black and wet, light brown and dry. when were the crabs cleaned and rebuild totally.
 

FishHunt23

Seaman
Joined
Jan 4, 2007
Messages
50
Re: Starting Problems

Plugs were gray and dry as I recall. Definitely dry and fairly clean (they've got maybe a couple of hours on them).

Carbs were rebuilt last year.

Thanks for the help!
 

FishHunt23

Seaman
Joined
Jan 4, 2007
Messages
50
Re: Starting Problems

Might also be worth noting that the engine idled at low speed and smoothly once I got it going. It ran exceptionally well throughout the RPM range, actually.

Was reading the FAQ starting thread. The one thing that caught my attention was "flooding due to failed float needle." When I got the engine going it did act flooded ... but why dry plugs if that's the case? I really have no idea how to check the float needle or even what it is beyond part of the carb.

Frustrating!

John
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Starting Problems

is your primer working. if i'm correct the carb does not have the choke butterfly, buy you have the solenoid, primer with the red handle, you push the key in and should hear it clik. in stead of restricting air flow to provide more fuel, the primer allow fuel in to the intake, the red handle is the manual setting, in line with the body of the primer is automatic.. and pushing in on the key allow fuel into the intake, 1/2 turn is manual and allows the fuel in. your primer solenoid may not be working, thus not choking the engine. did that make any sense?
 

StratosRob

Petty Officer 3rd Class
Joined
Sep 8, 2006
Messages
93
Re: Starting Problems

Do not use starting fluid. NEVER ! Has no lube in it.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Starting Problems

If you cranked for a long period and the plugs are still dry, its fairly obvious it's not getting fuel. You do not have a new fuel delivery system. Fuel still has to make it through the carbs. There is apparently some debris in the carbs or possibly in the primer system that's cutting off fuel flow. Rebuild time.
 

perkdp

Petty Officer 1st Class
Joined
Sep 25, 2002
Messages
237
Re: Starting Problems

What did you do to finally get it to start ?
Sounds to me like a flake of trash got hung in the line somewhere blocking gas flow. This engine has 2 carbs ... does the main feed split at the fuel pump to each carb ?

If you primed it through the carb throat with gas or ether, it should have said something if it was firing, unless the intake reeds/valves were stuck closed preventing vaccum.

Good luck
 

FishHunt23

Seaman
Joined
Jan 4, 2007
Messages
50
Re: Starting Problems

Tashasdaddy nailed it. The primer solenoid isn't working. I primed it manually today per the description given and it started realiably all day long. Great stuff from this site as usual. Thanks!
 
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