First Mac engine. Throttle cable atchment mystery

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Tim McElrath
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Joined: Tue Nov 15, 2016 11:55 am
Vintage Karting items owned: Mc90~somethjng engine. Still need to ID
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First Mac engine. Throttle cable atchment mystery

Post by Tim McElrath » Wed Nov 16, 2016 8:59 pm

First post, new to forum. I recently picked up my first kart and i believe its an ultramax something or other. To push it i picked up an unknown Mac kart engine. Its either a 91, 92, or 93. I ordered ot from a guy out of Fresno that hadnt gone through it yet and he wasnt quite sure which model it was. I just got my hands on it and i was planning on using macbobaust to figure it out but it seems that page has gone the way of the dodo. It has a BDC-14 carb and a tapered shaft with key slot. Also has a black flywheel cover. It does have the boost ports drilled but the are plugged with mini freeze plug looking things and painted over woth a stripe of what appears to be red RTV. Seems to be in decent shape. Has decent compression. The reason I am posting is because I am completely baffled on how to attach my throttle cable to the carb. The guy I bought the kart from cut me a deal without the engine. When i got the kart, the end of the throttle cable looks like he took wore cutters to it as there is nothing at the end of the cable.
I tried looking up throttle linkage attachment methods using the search feature but none of the pictures in any of the posts that i attempted to view were available. Any advice would be greatly appreciated. Even if its just pointing me in the right direction.

Thanks in advance!

~Tim

Rob Voska
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Joined: Fri Jun 15, 2007 9:04 am

Re: First Mac engine. Throttle cable atchment mystery

Post by Rob Voska » Thu Nov 17, 2016 9:00 am

Small aluminum clevis. Slot and cross hole in one end for a cotter key to go through the throttle shaft & a hole in the end with a set screw to lock cable in place. I'll post a picture later.

Welcome Tim.

Tim McElrath
Posts: 9
Joined: Tue Nov 15, 2016 11:55 am
Vintage Karting items owned: Mc90~somethjng engine. Still need to ID
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Re: First Mac engine. Throttle cable atchment mystery

Post by Tim McElrath » Thu Nov 17, 2016 12:08 pm

I appreciate it. Is that going to attach to the side where the idle adjustment screw is, or on the holy half moon side? Also, is the throttle cable mounted anywhere to the engine to prevent it fromjust pulling itself toward the engine instead of the cable pulling the throttle away grom the engine?

ted johnson
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Re: First Mac engine. Throttle cable atchment mystery

Post by ted johnson » Thu Nov 17, 2016 1:20 pm

Hi, Tim. The clevis can be attached either to one of the holes in the half-moon side of the shaft, or to a hole in the throttle pull on the opposite end of the shaft. You'll need a bracket to attach the loose end of the outer cable housing so that it is secure. There are air filter cups with cable attach fittings that screw into the three air inlet holes in the intake end of the carb, or there are brackets that screw to two of the four screws in the diaphragm cover of the carb. I hope someone can post a decent picture. All the ones I have are fuzzy or are from a bad angle. Welcome aboard. Ted

Tim McElrath
Posts: 9
Joined: Tue Nov 15, 2016 11:55 am
Vintage Karting items owned: Mc90~somethjng engine. Still need to ID
User Agreement: Yes

Re: First Mac engine. Throttle cable atchment mystery

Post by Tim McElrath » Thu Nov 17, 2016 2:44 pm

Fantastic! I really appreciate the rapid responses. Can you by any chance point me in the right direction to order said bracket? Or does anyone in here have one for sale? Please advise

ted johnson
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Joined: Fri Jun 15, 2007 7:59 am

Re: First Mac engine. Throttle cable atchment mystery

Post by ted johnson » Thu Nov 17, 2016 6:49 pm

Here we go! Most of the Mac stuff is no longer sold in the shops, though sometimes shops like Comet Kart Sales: www.cometkartsales.com might still have leftover stock. Usually we advertise on this forum in the for sale/wanted section, or another good move on your part is to join the www.vintagekarts.com forum and also advertise there in the for sale/wanted section. Those two resources, pus the vintage karts section of eBay are where most of us find these things. I'm sorry I can't help, as I always replace the Mac carbs with Tillotsons or Mikunis on the rare occasions when I build a Mac engine. Good hunting! Ted
P.S. I often use this search when I look for stuff on eBay. If you want magazines, erase that part of the search::
vintage kart -ad -ads -magazine -Briggs -magazines -gasket -gaskets -mario -zipper

REAR
Posts: 1222
Joined: Sat Jun 16, 2007 10:19 am

Re: First Mac engine. Throttle cable atchment mystery

Post by REAR » Thu Nov 17, 2016 7:12 pm

Tim,

Here is the clevis you need Ebay # 190841453165.

Here is a air fliter cup that will mount your throttle cable and air filter element. Ebay # 131999864590

R.E.A.R.

Tim McElrath
Posts: 9
Joined: Tue Nov 15, 2016 11:55 am
Vintage Karting items owned: Mc90~somethjng engine. Still need to ID
User Agreement: Yes

Re: First Mac engine. Throttle cable atchment mystery

Post by Tim McElrath » Sat Nov 19, 2016 4:28 pm

I appreciate all the help. Got it figured out! Can these engines be run either way? I have only seen them woth the drive shaft to the right of the kart, any way to run it to the left?

ted johnson
Posts: 1685
Joined: Fri Jun 15, 2007 7:59 am

Re: First Mac engine. Throttle cable atchment mystery

Post by ted johnson » Sat Nov 19, 2016 5:17 pm

Some karters have reversed the rotation of Mac engines, but it's not a recommended nor an easy procedure. In the early days, there were shafts available that bolted to the flywheel to allow a sprocket to be placed on the flywheel side. They are not safe, as they place too much stress on that end of the crank. Stick to the conventional way of driving off the PTO side of the engine. Ted

Tim McElrath
Posts: 9
Joined: Tue Nov 15, 2016 11:55 am
Vintage Karting items owned: Mc90~somethjng engine. Still need to ID
User Agreement: Yes

Re: First Mac engine. Throttle cable atchment mystery

Post by Tim McElrath » Thu Nov 24, 2016 12:03 am

Great sounds like more work than its worth. I appreciate all the help gents. I have never had this much assistance from a forum.

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