Carb wear on Model 70 Carter Carb

[rcupka]

Hi Guys, I am a Cub forum member that previously only had a 49 Cub , but recently picked up a Cub Cadet Model 70 that has sat for 20 years. (Also got a 154 Lo-Boy but that is a different forum)

When I took the carb off to clean it, I found a missing throttle plate screw, I took of the plates and shafts out and have seen both wear on the shaft and throttle plate where the plate was wobbling on the shafts remaining screw, but also on the throttle shaft where it rotates in the housing. It must have been running for quite a while like that and also appears to be a high time engine. (already has a+ .010 piston and rings in it)

I took the head off to inspect to see if there was damage to the valves or seats from where the brass screw was ingested but there does not appear to be any damage.

I can put in new screws on the throttle plate, but will the wear on the shaft diameter where it pivots case air leakage and loss of performance? I realize a 54 year old 7 hp Kohler is not a swiss watch, perhaps that amount of air leakage will not cause and performance degradation, have you had any experience with this?

I was looking at replacement carbs, there are no name brand likely imported knock-offs for anywhere from $17 - $40 buck out there but I worry about quality as well as performance. If you think I would be better off just replacing the throttle screws, gaskets, float valve , etc.... and sticking with the old Carter I would appreciate your opinion?

Thank You,
Dick Cupka

[Eugene]

I would use the carburetor and see what happens. The carburetor can be repaired, but very expensive.

I would be looking around for a spare parts tractor or engine. That engine was used by other lawn and garden tractor manufacturers.

I haven't had any success with the foreign made after market carburetors.

[rcupka]

Thank You Eugene, that sounds like good advise!

[rcupka]

[BigBill]

These throttle plate screws get staked on the threaded ends that stick out of the shafts.

I did notice the Chinese replacement carbs aren’t staked also.

My old 49 gmc van ate the throttle plate screws too. Took a licking and kept on ticking.

[BigBill]

Question, are the shafts loose in the bores.? You can take a flat nose punch and punch around the bore for the shaft gently to move material towards the center of the bored holes to tighten them up somewhat. A squirt of oil often during maintenance will stop some of the wear. Here’s my 70.

http://www.tractorshed.com/cgi-bin/gall ... os&cc=5&s=

[Bob McCarty]

If the Carter Carb has felt shaft seals like a Cub IH carb, replacing them will likely help. You might also check with Morgan at McDonald Carb and see if he has any of the replacement parts you need.

[BigBill]

Don’t forget to put a tad of oil on the shafts in the body.

[Eugene]

That engine was used by other lawn and garden tractor manufacturers.

The Carter N series carburetor was used on Kohler engines, 4 HP thru 14 HP and on a few larger Kohler HP engine.

I recently junked a John Deere riding lawn mower. I saved were the Carter N carburetor and rear tire rims.