Jump to content
Gumshu

Carb replacement

Recommended Posts

Gumshu

Hey guys, I just replaced the carb and fuel pump on my 310-8. I have it adjusted and it runs smoothly but it seems like I don’t have the same amount of rpm’s at full throttle. Anyone have any ideas? I got everything from the isavetractors guy. I do have an email into him but thought I’d stop here while I wait. I changed the carb and pump because I was getting fuel in the oil. 

Share this post


Link to post
Share on other sites
 
The Tuul Crib
40 minutes ago, Gumshu said:

Hey guys, I just replaced the carb and fuel pump on my 310-8. I have it adjusted and it runs smoothly but it seems like I don’t have the same amount of rpm’s at full throttle. Anyone have any ideas? I got everything from the isavetractors guy. I do have an email into him but thought I’d stop here while I wait. I changed the carb and pump because I was getting fuel in the oil. 

 Points condenser and plugs. .20  Gap on the points at top dead center . That's what I will try next 

Share this post


Link to post
Share on other sites
 
oldredrider

Try gapping the points at .020. It will work much better. 

  • Like 2
  • Haha 1

Share this post


Link to post
Share on other sites
 
Gumshu

Why would it need replaced if it was running fine with the exception on fuel in the oil previously? I’m not doubting anyone. I’m just trying to understand. 

 

Back story- I discovered fuel in the oil and the occasional back fire at shut down. A repair guy told me to replace the carb and pump. No previous issue with wide open engine rpm. I replace both and tune it as perfect as possible. I notice the rpm at full throttle are just not where they used to be “by ear” not measured by a gauge. I know, very scientific.  

 

What is the blade speed speed supposed to be?

Edited by Gumshu

Share this post


Link to post
Share on other sites
 
ELECTRORIC

Did you adjust the governor when you replaced the carb?

Share this post


Link to post
Share on other sites
 
Gumshu

I didn’t touch anything other than the carb and fuel pump. 

Share this post


Link to post
Share on other sites
 
oliver2-44

There is a wide open throttle stop as part of the linkage that is adjusted to set Max RPM.  While you may not have changed it, your new carb and corresponding linkage hookup might just be slightly different enough that this max rpm limiter needs to be checked. The carb mounting bolt holes are slotted, so if your new carb is shifted slightly different than exactly where the old one sat, that could be enough of a difference.   Sorry I don't have a good diagram to point to, so maybe one of the othe guys will jump in here with a better description or diagram.

  • Like 1
  • Excellent 1

Share this post


Link to post
Share on other sites
 
elcamino/wheelhorse

@Gumshu does your 310 have a Magnum 10 hp motor , if so no points. 

  • Like 2

Share this post


Link to post
Share on other sites
 
Gumshu

It is the magnum. 

Share this post


Link to post
Share on other sites
 
Gumshu

The linkage moves the full throw on top of the carb when the engine is off. When it’s running it barely moves when I work the throttle. The engine responds to the throttle, it just doesn’t move as it does when the engine is off. I’ll try for a quick video tomorrow. 

Edited by Gumshu

Share this post


Link to post
Share on other sites
 
dells68

The governor controls the throttle movement when the engine is running and will appear to reduce the travel of the throttle linkage.  Your cable should have the same range of motion, running or not, the governor manages the throttle linkage movement.

  • Like 2

Share this post


Link to post
Share on other sites
 
Anglo Traction
10 hours ago, Gumshu said:

Why would it need replaced if it was running fine with the exception on fuel in the oil previously? I’m not doubting anyone. I’m just trying to understand. 

What is the blade speed speed supposed to be?

Depends what Deck you are running!.

Did calcs on my 36" RD to check bearing specs and gave these results-

 

Full engine speed (recommended) 3500 rpm, PTO pulley 4" dia, Mower Deck Driver pulley 4" dia , Driven 4" driving 14inch dia centre Blade = tip speed of 145.83 MPH (@ 3500rpm)

Outer 12inch Blades with 3 inch Pulleys= (3500rpm x 1.25) tip speed of 156.25 mph @  4375rpm.

  • Like 1

Share this post


Link to post
Share on other sites
 
Gumshu

I guess the Next step is checking engine rpm. I just ordered an hour meter/tach. That’ll be good enough to tell me if I’m getting 3500 out of the engine. I’ll keep you guys posted. 

Edited by Gumshu

Share this post


Link to post
Share on other sites
 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...