The Kart Engine Thread

[rwoods]

I have a lot to learn.

I fired up my little red 101B today. (pictures here http://www.arboristsite.com/chainsaw/172208-7.htm and in MAC thread). I don't have enough hands between stabilizing the bench and cranking it. I am glad I only had 10ccs of fuel in the line after the carb quit bubbling air as when it cranked it screamed until the fuel ran out. I just barely had the throttle above idle. I put another 10 ccs of fuel in it this time leaving the carb at idle - same result. Do you think the vacumn is overcoming the throttle spring (I don't have any linkage)? The spring seems to be of normal tension. Or is there sometime else I am missing? It gulps the fuel down in seconds although it seems like an eternity as I gather my wits and remind myself there is no off switch. Thanks for your help. Ear protection is going to be a must with this baby. Ron

 

[Eccentric]

I fired up my little red 101B today. (pictures here http://www.arboristsite.com/chainsaw/172208-7.htm and in MAC thread). I don't have enough hands between stabilizing the bench and cranking it. I am glad I only had 10ccs of fuel in the line after the carb quit bubbling air as when it cranked it screamed until the fuel ran out. I just barely had the throttle above idle. I put another 10 ccs of fuel in it this time leaving the carb at idle - same result. Do you think the vacumn is overcoming the throttle spring (I don't have any linkage)? The spring seems to be of normal tension. Or is there sometime else I am missing? It gulps the fuel down in seconds although it seems like an eternity as I gather my wits and remind myself there is no off switch. Thanks for your help. Ear protection is going to be a must with this baby. Ron

Wire the throttle arm in the idle possiton to be sure. Look through the carb throat and see if the throttle is indeed closed at idle. Could be adjusted quite a bit past closed. Doesn't take much to make an unloaded engine rev up. If you close the throttle and wire it in that possiton and the engine still revs to the moon........................then you have an air leak somewhere my friend.

You can make an OH ####!!!!!! handle out of a couple of zip ties attached to the plug cap. If the engine's revving towards destruction............pull the hell out of the zip tie to get the plug cap off of the plug. You may break a spark plug wire, but that's FAR better than throwing a rod...

 

[cpr]

Uh... Well, I don't know how you mounted it, but if the head was finger tight, any chance the stuffer is the same and that's your air leak?

Like Aaron said, what's the throttle butterfly doing?

 

[rwoods]

After I posted I started thinking air leak at the stuffer but I don't know. The butterfly is barely cracked - don't know when running as it :msp_scared: me bad then was done before I could react. I have it bolted through the stuffer to my bench. I'll either build a leak tester and/or a shorting wire to shut her down. It definitely sounds like it is hitting rpm levels previously unknown to me. Thanks, Ron

 

[cpr]

Again depending on how you mounted it, is there an oil tank? If not, do you have a saw stuffer in there and it's getting a big gulp of air through the auto-oiler impulse port?

 

[rwoods]

Kart stuffer - no oil hole yet. Ron

 

[NORMZILLA44]

Kart engine, I just love the name what a ring to it!

 

[Brian Thomas]

<iframe title="YouTube video player" width="640" height="390" src="http://www.youtube.com/embed/qTX_a5Gvc2I" frameborder="0" allowfullscreen></iframe>

That is our kart . That motor is a AH61 that is .060 over and has a stroker crank in it .

I found this site while doing some surfing .

Check out our site

Black Dog Vintage Racing

We run Power Products exclusively .

Brian

 

[blsnelling]

That is our kart . That motor is a AH61 that is .060 over and has a stroker crank in it .

I found this site while doing some surfing .

Brian

Beautiful kart there Brian! You could have a nuclear explosion in that engine and it wouldn't blow the head off Welcome to the forum

 

[Trever]

West Bend Model 2736

The West Bend model 2736 is essentially a model 700 with a shorter stroke (105cc). This is what my late 1950s Strunk Big Machete has on it. I will post the specs when I find them. Have a blessed abnd happy Thanksgiving.

 

[cpr]

Missed out on a 48890b carb with a GEM elbow and a REED sloper intake on feebay tonight. Oh well, whoever got them had to open their wallet a little anyway :msp_biggrin:.

I got some trees to bark up for that stuff...

 

[leeha]

I watched that as well.
But it wasn't me.

I have an intake for the BDC carb
for my next kart saw. Thanks the Jacob J.



Lee

 

[cpr]

Cleaning up the shop tonight and had to take a pic of 362cc of American muscle, two of which are kartsaws.

View attachment 210849

 

[Rounder]

Nice to see you're still at it. I've got two boxes of big yellow in the shop waiting for me....if I ever get a spare moment.

 

[rwoods]

As some may recall, my kart saw's connecting rod would bind when the saw was turned on its side. I have now removed all of the bearings. Is there anything this neophyte should know before installing any of the new bearings? Also is there any chance a crank could be slightly bent? If so, how can this be detected before reassembly? The connecting rod appears to be nice and straight when placed against a straight edge. The wrist pin bearings don't seem any looser than the new ones and the main bearings didn't appear to have any unusual slop. The wrist pin measures between .4985 and .499. Thanks, Ron

 

[cpr]

I suppose it's possible. I don't know how they made these old cranks. If they're interference fit for the rod journal like modern cranks the throws might be out of clock with each other???

Good luck Ron, hope you get it going.

 

[leeha]

Ron, When the motor is together, Do you have a bit of
side play on the rod. Is the crank floating in the case bores.
Sounds like the crank is moving. These cranks are a cast
crank. If it were out of time it would be twisted and you would
know it no matter the position of the saw.




Lee

 

[rwoods]

Ron, When the motor is together, Do you have a bit of
side play on the rod. Is the crank floating in the case bores.
Sounds like the crank is moving. These cranks are a cast
crank. If it were out of time it would be twisted and you would
know it no matter the position of the saw.


Lee

Lee, before disassembly I didn't detect any crank play. The rod had enough side play to bind. Should I have the crank's rod bearing surface checked by a machine shop? I have a set of new needle bearings which I'll install with the rest of the bearings. Thanks, Ron

 

[leeha]

Did the rod bind on the crank with the old needles.
I would take the crank out and assemble the rod to
the crank and see if it binds. Try this with the new
needle bearings as well as the old ones. The rod
should spin around the crank nice and smooth no
matter what.



Lee

 

[rwoods]

Lee, it would bind with the old needles. The rod would slide to the side and bind. You could give it a little jerk and it would pop and free itself. You could also just push the rod back over with your thumb. I disassembled the entire engine some months ago and bought all new seals and bearings. I had a little time tonight so I pulled all the old bearings. I guess I'll just go ahead and install the new and see how everything fits. Anything I should know first? Thanks, Ron