# 610 problem



## 610-run-like-sh

OK...boys...I got one for yah. I have a 610...year don't know. I inherited it from my wife's family farm and it runs like ****. I have replaced plugs, points, cond, rotor, distr cap, plug wires, almost everything. It has good spark and it runs good on slow speed. When you put it in fast speed and work the engine...it sputters and pukes and torks me off. I have done a carb rework and don't know where to begin. How is the exact procedure to set the carb? Anyone? I have some manuals that say there was an service bulletin on this thing back in 1977 explaining that the float adjustment should be 11/4" and that some fuel pumps may experience high gas pressure and flood the carb. It should be around 2-3 #'s. If it is more, they say to get a lighter fuel pump spring. What about timing? should it be checked if it runs good on low speed and low idle? Anything would be a huge help.


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## Milwaukee

Is this front loader or farm tractor?

You say 610? It ford tractor with 34 hp engine 4 incline? or it diesel engine?


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## 610-run-like-sh

sorry guys...It is a Melro Bobcat 610 skid steer loader with the Wisconsin engine- gas


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## Milwaukee

It v4 engine? how much cylinders it have?

How much hours on that engine?


Bad new it get hard time find parts for that engine.


Did you try spark test on that when try rev engine do you see spark not work right or flick?


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## 610-run-like-sh

yes..V4 engine. 4 cyl

lots of hrs...can't say how many...it was overhauled back in like mid 80's I guess

I will take my timing light and see if the spark is good on all cyl's tonight and report back.

thanks


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## Milwaukee

Can you check compressor on 4 cylinders. I suspect too old plus have many hours on that so it almost worn out soon but if 4 cylinders say 100 or up PSI then I am surprise it could last for another years.

Do you have any ATF fluid like auto transmission fluid? try dump that in carb not use all just little enough to get engine smoke. Then dump half of atf in gas tank that should help but not sure.


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## hydro_37

Check the timing. There are a ton of parts still available for that motor. The wisconsin is a great motor. Is there a chance you have water in the gas?


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## 610-run-like-sh

I have to believe my gas is good...it has been replaced with fresh gas...I will reset the points tonight to factory specs, check the timing and also check to see that all (4) plugs fire on high rpm. I am just thinking I have a fuel/air mixture problem on the carb and it is not set proper. I have only 1 screw on the carb as it is a Zenith carb. The Bobcat guy told me today to operate the bobcat until warm up is complete, open the choke completely, speed the rpm to the fastest it will go and adjuest the air screw until you get the highest rpm out of it and then an 1/8 turn more (richer)...that should be real close....does any of this make sense to anyone?


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## 610-run-like-sh

point gap was just a tid bit off, slightly..timing was also off a bit....runs better, but still loads up and some slight missing, choking popping....seems like I have to adjust the choke quite a bit to make it run well. I may just have to live with it I guess.


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## kriedy

*Bobcat 610 Carb Problem*

I Have The Same Problem As 610 Run Like Sh. My Bobcat Will Only Run Fast If The Choke Is On. It Idles Fine. Any Solutions?


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## hydro_37

Set your carb like the Bobcat guy said too. You should be able to find a carb diagram online for pictures too.


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## Drottlawn

kriedy;517536 said:


> I Have The Same Problem As 610 Run Like Sh. My Bobcat Will Only Run Fast If The Choke Is On. It Idles Fine. Any Solutions?


You are lean at the high end. That is why you have to choke it to keep it running. It richens the mixture. This is caused by dirty carb, out of adjustment carb, or timing. My guess is on the carb or intake leak. Try spraying starting fluid around the intake gasket areas and see if the rpm changes, if it does you have a bad intake gasket. Do this with a cool engine!!!!!! Hot, it may get a little hotter if you know what I mean.


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## Drottlawn

610-run-like-sh;515310 said:


> OK...boys...I got one for yah. I have a 610...year don't know. I inherited it from my wife's family farm and it runs like ****. I have replaced plugs, points, cond, rotor, distr cap, plug wires, almost everything. It has good spark and it runs good on slow speed. When you put it in fast speed and work the engine...it sputters and pukes and torks me off. I have done a carb rework and don't know where to begin. How is the exact procedure to set the carb? Anyone? I have some manuals that say there was an service bulletin on this thing back in 1977 explaining that the float adjustment should be 11/4" and that some fuel pumps may experience high gas pressure and flood the carb. It should be around 2-3 #'s. If it is more, they say to get a lighter fuel pump spring. What about timing? should it be checked if it runs good on low speed and low idle? Anything would be a huge help.


Does it put out black smoke when it sputters? If so, it is to rich. This can be misadjustment of the carb or your fuel issue you stated. I don't know on these engines, but do they have timing advance. I don't think so, but if it does check to see if the timing advances as rpm goes up. If it doesn't, this will cause this problem.
If no smoke and pops out carb, it is to lean. Check the intake as I stated to the other post.
This is all I can think of!:salute:


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## 610-run-like-sh

it don't puff black smoke at all...when it misses or cuts out on high speed/ fast idle...it just cuts out...no smoke. The timing does advance and it is set at oh....I think 23 deg's b4 tdc as the manual states....I think I have a real bad carbon issue in the cylinders and a slight miss adjustment on the carb. The carb is completely clean and a new carb kit installed. When I set the carb air/fuel screw on fast idle with the variable speed at the low position...it runs good...when the engine and hydraulic oils, etc warm up and I put the variable speed to fast or high and use like...."road gear" if yah will....then she cuts out when a load is worked...I think I just need to use some good fuel additive and clean the cylinders up and back the air screw out another 1/8 turn or so and I will have er. Hell who knows. This thing is worse to figure out than my wife.


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## Kramer

I have the same isue with a 310 bobcat--- 16hp kohler single cylinder. Run at half speed or no load its fine--load it up and it seems like its pouring gas down the carb. The way it happens its hard to say if the spark is cutting out and then cant keep up or just over loading w/gas. Either way, its a total failure and then starts right back up w/no issues.

Adjusting the carb screws won't help...at least not a lot. I had a bad head gasket, replaced that, have good compression and the same problem. One problem I have is not fuel related, but I have a bad engine ground. Not sure if its related, but my points, condensor, coil, and carb are all new---no change (the previous guy had all that changed by Bobcat). 

Anyway, I haven't checked the fuel pump pressure but I have worked hard looking at the governor, linkage, and so on..... I need to fix the grounding but things like pickup from the fuel tank and so on havent been checked yet--its a second machine I dont need.

Let me know if you find the issue because it seems like several people have the same thing going on....and w/different engines.


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## 610-run-like-sh

OK..I will...you may want to chck the pressure of the gas pump. Bobcat makes mention of a problem on some fuel pumps when loading the carbs and too much pressure...they mention somewhere around 3#'s I think.


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## powerjoke

she is just runnin lean,

and like Drott said take some carb cleaner and spray around on the entire intake(where a gasket should be) anything from the buterfly down

if you have to 1/2 choke the thing i would believe it is more of a leak than a adjustment.....you do understand that "unscrew" on the fuel screw is richen 

i don't know why you think you have carbon buildup?. most of the time you'll actually get a upper end knock, it wont hurt anything to clean it up just incase, all you have to do is talke a big glass of water (like 1 quart) and take the breather off so you can pour it straight into the intake and take one hand and grab the throttle linkage or butterfly and then pour the water slowely into the throttlebody and revving it more and more as you pour and eventually you will pour verry quickly and the buterfly will be at W.O.T.


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## 610-run-like-sh

been awhile since the last post- I had ordered a new Zenith carb and bolted it to the Wisconsin engine and the problem was fixed until last week- now it will start and everything and when u push the choke back in or (off) it will die out? It got warm again this week and is there some major mods (jetting) I need to do now? something get into the carb? did something come loose and sucking air?


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## XplowX

Sounds to me like the jets are getting plugged up. Is there a fuel filter on the machine??. Does the machine have a steel fuel tank?


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## menofiron

My father ran a 600 bobcat(basically the same machine) for 30 years. He thinks it is either getting water in the gas, possibly from condensation, or your fuel pump is bad. In hot weather they will vapor lock very easily if the fuel system isn't just right. Try running some isopropyl alcohol in it.


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## Tadpol

Milwaukee said:


> Is this front loader or farm tractor?
> 
> You say 610? It ford tractor with 34 hp engine 4 incline? or it diesel engine?





menofiron said:


> My father ran a 600 bobcat(basically the same machine) for 30 years. He thinks it is either getting water in the gas, possibly from condensation, or your fuel pump is bad. In hot weather they will vapor lock very easily if the fuel system isn't just right. Try running some isopropyl alcohol in it.


I don't know how to make a post but hopefully someone will see this and be able to help a few weeks ago I lost spark on my 610 bobcat well I got spark back and set timing and ran good the other day I was using it and it lost power and would run like crap I'd advance timing and it would run good for about a min then I'd have to turn dist again and it keeps doing it any ideas?


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## Mountain Bob

Well,they are known for the distributor gear pin shearing. But this site may be of better help for you,lots of 610 and wisconson engine stuff--
https://www.smokstak.com/forum/


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## Tadpol

Mountain Bob said:


> Well,they are known for the distributor gear pin shearing. But this site may be of better help for you,lots of 610 and wisconson engine stuff--
> https://www.smokstak.com/forum/


Ok thank you that's what I was thinking but I figured if it sheared off it wouldn't run at all thanks for the reply!


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