Sport 40 Help

[BobGutsell]

Here's my 2 cents.

1. The pressure line looks too small and that loopy kink thing in it won't be doing you any favours. I like a pressure line about 1/8" I.D for all nitro engines. Trust me!

Hypothesis: the boat runs 2-3 laps before it runs out of fuel pressure due to a kinked or insufficient pressure line.

2. Where is the fuel pickup in the tank? Is it a Klunk in the front of the tank or do you have a solid pickup tube that curves to the bottom rear of the tank.

Hypothesis: the Klunk is on a tube inside the tank with the klunk at the front of the tank. When the fuel level gets low the fuel is forced to the rear of the tank and leaves the klunk almost dry, resulting in lost fuel.

Having the Tank that close to the carb isn't good, but I wouldn't have thought that would cause fuel starvation after a few laps. I would think it would be more of a chrinic problem of not fully revving out or something.

Hope that helps.

Cheers

Bob

 

[Mike Larson]

Gonna inject another theory.... How many tanks on the motor Garson?.... thats a disc rotor engine, and, I have thoughts the clearance may need reset? Something is heating up, allowing air, and leaning the boat out under load.......

I did, replace all the fuel lines to my bigger boats to the larger brass, to aid in the draw.......

Getting water?.... My first pass, is always to check for the little stream shooting skyward.......

I used push rod seals on the exit of the steering rod too, with drains in the port rear of the transom area..........

Now, that you have enough to rip the boat apart, chasing for the problem is always the fun part..... be good, Mike

 

[GarsonConnor]

Thanks guys fpr all your help and suggestions. I will test each suggestion and update, in the mean time here are a few pics.

Garson

The carb looks very close to the tank Garson. If you can't shove the tank farther fwd. get a flex tank and soften up the front with a heat shrink gun to clear the cowl. The few P.T. spt 40's I've seen have the main tank in the starboard side of the hull(near the balance point). I think a hopper tank would be a good idea. Once the fuel starts getting low it may start sloshing around and getting air bubbles in the fuel. I have a 60 size hydro that shows the same symptoms- slows after about 4 laps(16 oz main/ no hopper). Just my .02c

Glenn

The tank is as far forward as I can get it and still close the cowl.

Flex tank ????

Looks just like a standard tank dimesion wise but is made of a somewhat clear soft plastic... as Glenn said, you can use a heat gun to CAREFULLY to shape it to fit under the cowl....when it cools it holds the shape you made....reasonably cheap fix! It really is a good idea to use a hopper tank, though i havent put one in my boat....yet!

It really is a good idea to use a hopper tank, though i havent put one in my boat....yet!

:lol: :lol:

Show us a pic of the strut from inside the boat looking straight down

Finaly got around to taking the pic.

 

[GarsonConnor]

Here's my 2 cents.

1. The pressure line looks too small and that loopy kink thing in it won't be doing you any favours. I like a pressure line about 1/8" I.D for all nitro engines. Trust me!

Hypothesis: the boat runs 2-3 laps before it runs out of fuel pressure due to a kinked or insufficient pressure line.

2. Where is the fuel pickup in the tank? Is it a Klunk in the front of the tank or do you have a solid pickup tube that curves to the bottom rear of the tank.

Hypothesis: the Klunk is on a tube inside the tank with the klunk at the front of the tank. When the fuel level gets low the fuel is forced to the rear of the tank and leaves the klunk almost dry, resulting in lost fuel.

Having the Tank that close to the carb isn't good, but I wouldn't have thought that would cause fuel starvation after a few laps. I would think it would be more of a chrinic problem of not fully revving out or something.

Hope that helps.

Cheers

Bob

Hello Bob,

1- removed the loop, I'll get larger line.

2- pick up is a solid brass pickup and is in the rear left coner not touching the bottom or sides.

Thanks for your input.

Garson

 

[GarsonConnor]

Gonna inject another theory.... How many tanks on the motor Garson?.... thats a disc rotor engine, and, I have thoughts the clearance may need reset? Something is heating up, allowing air, and leaning the boat out under load.......

I did, replace all the fuel lines to my bigger boats to the larger brass, to aid in the draw.......

Getting water?.... My first pass, is always to check for the little stream shooting skyward.......

I used push rod seals on the exit of the steering rod too, with drains in the port rear of the transom area..........

Now, that you have enough to rip the boat apart, chasing for the problem is always the fun part..... be good, Mike

Mike thanks for your thoughts. I'm not sure how many tanks have been run thru the motor. When I purchased it from the previous owner I was told that he had new bearings installed and he just put it in a zip lock bag until I got it. I since have run at least 5 tanks thru it.

Well I went to the lake this weekend to try the suggesions fro you guys and it seemed to run with no problem, so I will try it again at this weekend D3 race in Miami.

Thanks

Garson

 

[P THOMAS]

HI That SuperSport45 boat you have there is a real old one, only about 30 where built with the wood engine well and built in radio box like that. 90-91. Does the sticker in the back have a build date?

That gold head CMB is a drum rotor engine so bad clearance should not be a problem and if it does have good bearings the motor should run ok. Is the plug ok after it dies?

 

[GarsonConnor]

HI That SuperSport45 boat you have there is a real old one, only about 30 where built with the wood engine well and built in radio box like that. 90-91. Does the sticker in the back have a build date?

That gold head CMB is a drum rotor engine so bad clearance should not be a problem and if it does have good bearings the motor should run ok. Is the plug ok after it dies?

Hello Phil the sticker does not have a date. I ran it this weekend at the D3 race in Miami and it was just a waste of $15 entry fee because it did the same 2-3 hot laps then died. The plug is always good when it dies and just fires back up. I'm at my witts end with this boat and I am contemplating selling it, it's just such a beautiful little boat and really flies when it is running the couple laps when it does run. My wife is threating to mash it with a hammer if I spend any more money on it. :lol:

OH by the way I manage to get a 2nd place win over all this weekend. Talk about luck :lol:

Garson

 

[Ray Sametz]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

 

[SayMikey]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

I did not reread this whole thing but did you check the pipe fitting to be sure it is not plugged up. Id also consider running it without the cowl and look for any water spray. When you empty the fuel tank doea it completly drain the tank

 

[GarsonConnor]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

OK I'll try a another new pack this Sun. when me and the guys get together to run our boats and let you know what happened.

 

[GarsonConnor]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

I did not reread this whole thing but did you check the pipe fitting to be sure it is not plugged up. Id also consider running it without the cowl and look for any water spray. When you empty the fuel tank doea it completly drain the tank

Yep I checked the fitting, it's clear. When I empty the tank it still has a little fuel in it unless I get someone to hold the boat up and lean it to the left but this still does not completely empty it because the pickup is not on the very bottom of the tank nor is it touching the wall of the tank.

I really think that it needs a sump tank but am not 100% sure, and am not cleared to spend $100 for a custom SS tank to test my theory.

Garson

 

[jetpack]

Garson you mentioned using a solid brass pickup? Do you mean you are using a brass tube for your pickup or fuel tubing to a solid brass clunk that comes with the tank kits?

If using the flex hose inside the tank, could it be there's enough slack in it for it to start bouncing out of the fuel load after a couple laps?

 

[SayMikey]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

I did not reread this whole thing but did you check the pipe fitting to be sure it is not plugged up. Id also consider running it without the cowl and look for any water spray. When you empty the fuel tank doea it completly drain the tank

Yep I checked the fitting, it's clear. When I empty the tank it still has a little fuel in it unless I get someone to hold the boat up and lean it to the left but this still does not completely empty it because the pickup is not on the very bottom of the tank nor is it touching the wall of the tank.

I really think that it needs a sump tank but am not 100% sure, and am not cleared to spend $100 for a custom SS tank to test my theory.

Garson

You just need a sullivan 1-2 tank

 

[GarsonConnor]

Garson you mentioned using a solid brass pickup? Do you mean you are using a brass tube for your pickup or fuel tubing to a solid brass clunk that comes with the tank kits?

If using the flex hose inside the tank, could it be there's enough slack in it for it to start bouncing out of the fuel load after a couple laps?

Not using the hose and clunck, just brass tubing bent back to left corner of tank but not on bottom or touching sides.

 

[GarsonConnor]

Garson, you got nothing to lose, humor me and try another battery pack. You can try cycling your pack or just borrow one from a buddy.

I did not reread this whole thing but did you check the pipe fitting to be sure it is not plugged up. Id also consider running it without the cowl and look for any water spray. When you empty the fuel tank doea it completly drain the tank

Yep I checked the fitting, it's clear. When I empty the tank it still has a little fuel in it unless I get someone to hold the boat up and lean it to the left but this still does not completely empty it because the pickup is not on the very bottom of the tank nor is it touching the wall of the tank.

I really think that it needs a sump tank but am not 100% sure, and am not cleared to spend $100 for a custom SS tank to test my theory.

Garson

You just need a sullivan 1-2 tank

I'll give it a try this weekend before I get rid off it.