Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

phillobbezoo

Briggs Vanguard in a powermax

Recommended Posts

phillobbezoo

I’m curious if anyone has any experience with the 23hp vanguard motors that were sold as a repower for the pmax series tractors. This past winter I went in the barn and seen a puddle under the tractor after checking it out it was gas and oil. The fuel shut off failed and the gas filled the crank case, or at least that’s what I assume. So I drained the oil unhooked the gas line and forgot about it till a week or 2 back. I ordered a rebuild kit for the carb which consisted of all new orings needle seat float and gaskets, I also installed a fuel shut off. Rebuilt the carb and it fired right up and ran great, so I grabbed the baby and off we went, didn’t make it very far till it started missing and blowing black smoke, shut the fuel off and it seemed to clear up enough to get it back to the barn. Pulled the carb to make sure the needle was closing. Pulled carb back apart to make sure I didn’t miss anything put it back together fired up and ran great but only made it a few hundred feet away from the barn and the same thing. I also put a new fuel pump on it but same thing. I’m. Not sure what to look for next any help would be greatly appreciated, thanks 

Share this post


Link to post
Share on other sites
ShaunE

Phil I have a close friend that has one of these in a 9020 with an Ark 700 loader.  The machine works flawlessly all the time.  So good that I have made the statement out loud that I would repower rather than rebuild if my Onan grenades.

This definitely sounds like a fuel delivery issue but it sounds like you have the bases covered.  Fuel cap vented, pickup tube in the tank intact, new lines & filter, if new pump is impulse is the integrity of the impulse line good?

If you have the means, you could try running the carb through an ultrasonic cleaner.  I've had great results with mine.

  • Like 1

Share this post


Link to post
Share on other sites
GregB

+1 on the ultrasonic cleaner.  Had a troublesome Tecumseh carb on a snow blower.  They are notorious for scaling up small passages.  Used a Harbor Freight ~$79 unit, and the purple water based cleaner from Home Depot. It is for all metals.  Worked good for me.

When it finally is warm enough to work in the shop, going to set-up and run my pile of briggs carbs thru the cleaner, and maybe have a re-built or two on the shelf when I need them. 

  • Like 2

Share this post


Link to post
Share on other sites
Talntedmrgreen

Seems to be overfueling.  I would look at the air flow.  Does it have trouble running with the air clean off?  We will have to look at the internal carb air ports.  I'm not familiar with these motors, but is it possible the crankcase breather has been plugged since the fuel/oil issue?  Sounds like it may be building pressure, if it's not a rich condition.

Share this post


Link to post
Share on other sites
MARK (LI)

Sounds like it could be the fuel itself...drain out the gas and put in a small amount (in case you have to empty it out)...add a little seafoam...it's a good time to change the fuel lines themselves also

Share this post


Link to post
Share on other sites
Talntedmrgreen
5 hours ago, MARK (LI) said:

Sounds like it could be the fuel itself...drain out the gas and put in a small amount (in case you have to empty it out)...add a little seafoam...it's a good time to change the fuel lines themselves also

If it was the fuel I think it would have a difficult time starting and running at all.  The symptoms are identical to a flojet carb with a cracked float.  Phil says he has put a new float in with no change, however, so something else is causing a rich condition after the bowl has had time to fill.  With a new needle and seat, that shouldn't be it, but I have had flojet kits where the new needle simply didn't work, so I had to revert back to the old needle.

 

I"m not sure what the return line setup on this looks like...I know the Onans would sometimes do this until the return line elbow ID was increased, after converting to 12V pump. 

Share this post


Link to post
Share on other sites
MercerRec

Was the needle valve rubber tipped and what material was the seat?   I'm not familiar with those carbs, but I would check the new needle vs the old needle as well as verifying the float height.  The rubber tipped needles that I see on outboard motors are more sensitive to ethanol than the all metal ones.  Have also seen where a brass seat is replaced but requires a slightly different height float height adjustment when installed.

Just curious but how much is a brand new oem carb?  I recently went that route on a PITA motor that was giving me static.  The rebuild kit without float alone was 100 and the brand new carb was just over 200.  

Share this post


Link to post
Share on other sites
MARK (LI)
28 minutes ago, MercerRec said:

Was the needle valve rubber tipped and what material was the seat?   I'm not familiar with those carbs, but I would check the new needle vs the old needle as well as verifying the float height.  The rubber tipped needles that I see on outboard motors are more sensitive to ethanol than the all metal ones.  Have also seen where a brass seat is replaced but requires a slightly different height float height adjustment when installed.

Just curious but how much is a brand new oem carb?  I recently went that route on a PITA motor that was giving me static.  The rebuild kit without float alone was 100 and the brand new carb was just over 200.  

I am pretty sure that all the tips are now made of something other than metal...not sure if it actually rubber, though......I was just looking for a rebuild kit or replacement for a 14HP Vanguard...the rebuild kit is about a 150 bucks...the carb is about $230, but they are just not available...Briggs sent me a list of guys who handle "antique" parts...if you re interested in it send me a PM and I will send it to you

Share this post


Link to post
Share on other sites
phillobbezoo

 

23 hours ago, ShaunE said:

Phil I have a close friend that has one of these in a 9020 with an Ark 700 loader.  The machine works flawlessly all the time.  So good that I have made the statement out loud that I would repower rather than rebuild if my Onan grenades.

This definitely sounds like a fuel delivery issue but it sounds like you have the bases covered.  Fuel cap vented, pickup tube in the tank intact, new lines & filter, if new pump is impulse is the integrity of the impulse line good?

If you have the means, you could try running the carb through an ultrasonic cleaner.  I've had great results with mine.

Not sure how long your friend has had his vanguard but I will never buy another, I bought this tractor with the repower already done, and do not know how many hours are on it, but since day one it has been a P.I.T.A. Infact because of this motor I would rebuild an Onan over one of these if that was my only choice for a repower.

Fuel cap is vented good, pick up in the tank looks good, I ran the motor with out the pump on and I can feel it pulsing, the impulse line is very short, 2” tops.

Unfortunately I do not have access to an ultrasonic cleaner.

14 hours ago, Talntedmrgreen said:

Seems to be overfueling.  I would look at the air flow.  Does it have trouble running with the air clean off?  We will have to look at the internal carb air ports.  I'm not familiar with these motors, but is it possible the crankcase breather has been plugged since the fuel/oil issue?  Sounds like it may be building pressure, if it's not a rich condition.

I haven’t ran it with the air cleaner off, I’ll try that tomorrow before I pull the carb again. I’ll bring it with me tomorrow to get another set of eyes on the carb itself. I checked the breather and it’s a read style breather and it all seemed fine to me🤷‍♂️.

 

14 hours ago, MARK (LI) said:

Sounds like it could be the fuel itself...drain out the gas and put in a small amount (in case you have to empty it out)...add a little seafoam...it's a good time to change the fuel lines themselves also

The gas is new, I’ll grab some new fuel line tomorrow and replace them all.

 

9 hours ago, tadams said:

If it's over fueling you sure the fuel return line isn't plugged

This particular carb does not have a fuel return like the Onan, I have seen other carbs off these vanguard motors that have a return line but this one does not.

 

7 hours ago, MercerRec said:

Was the needle valve rubber tipped and what material was the seat?   I'm not familiar with those carbs, but I would check the new needle vs the old needle as well as verifying the float height.  The rubber tipped needles that I see on outboard motors are more sensitive to ethanol than the all metal ones.  Have also seen where a brass seat is replaced but requires a slightly different height float height adjustment when installed.

Just curious but how much is a brand new oem carb?  I recently went that route on a PITA motor that was giving me static.  The rebuild kit without float alone was 100 and the brand new carb was just over 200.  

The needle is rubber tipped, it seats against plastic. I run ethenal free gas in all my tractors to avoid the issuies caused by the ethenal. The rebuild kit was just shy of 100$, if I remember right a oem Nikki carb was north of 300, I could be wrong tho. The float is not adjustable either. 

 

8 hours ago, Talntedmrgreen said:

If it was the fuel I think it would have a difficult time starting and running at all.  The symptoms are identical to a flojet carb with a cracked float.  Phil says he has put a new float in with no change, however, so something else is causing a rich condition after the bowl has had time to fill.  With a new needle and seat, that shouldn't be it, but I have had flojet kits where the new needle simply didn't work, so I had to revert back to the old needle.

 

I"m not sure what the return line setup on this looks like...I know the Onans would sometimes do this until the return line elbow ID was increased, after converting to 12V pump. 

I did my best to check the needle and seat, blow in the fuel intake line with the carb right side up, turned it over blew till I was blue in the face no air got in.

I appreciate the help guys, I’m headed to Josh’s tomorrow and I’m bringing the carb along, maybe he’ll see something I don’t. In the mean time any other ideas would be appreciated, although not sure where else to look.

Edited by phillobbezoo

Share this post


Link to post
Share on other sites
Rfp55

With viton tipped carb needles - some, if not all, require "hammering" softly against the seat with a screwdriver handle. Might depend on how long they've been stored on the shelf hardening up. That's fixed farm tractor carbs for me. Also was when original brass needle, before kit was put in didn't leak. Do not know vanguard engine- but does it have a vacuum operated fuel pump? If so, that is a spot to see. Bad diaphram.

I had had tractor carbs' brass floats with solder seams shrink enough at somewhere around -38°F to fill with gas, with no apparent entry point. Drilled two holes in to dump gas and flush and resolder up. No problem after. Carb & fuel pump about only chances I think - crankcase breather, an oil sentry switch, or oil filter adapter could let it escape but not mix gas into crankcase to overfill. Some of my (Briggs?) engines after sitting awhile, have the oil dipstick read and inch or two too high until you wipe and recheck - then it was OK. Other ones like Kohler's never do that capillary climbing or whatever goes on. There are mysteries.

Share this post


Link to post
Share on other sites
s_stephen

have you checked the valve lash? the vanguard engines are notorious for the valves getting out of adjustmet. i belive the briggs manual states that every one hundred hours to re adjust the valves. i have seen the valves be .020 out of spec which will greatly reduce the amount of air getting into the engine or exhaust getting out. the valve setting is .004 to .006 for both intake and exhaust with piston at tdc on compression stroke.

  • Like 4

Share this post


Link to post
Share on other sites
TimJr

What type of fuel pump is being used?  If you have an electric pump, you may need a fuel pressure regulator to drop pressure down - could be pushing the needle off the seat?  That wouldn't explain finding the crankcase flooded while in storage, but would explain it starting, running, but then smoking and flooding out.

Do you have a laser temp gun?  Are both cylinders running?

Share this post


Link to post
Share on other sites
Ronald Hribar

I had to put a pressure regulator on mine with electric pump

was a low pressure pump 1 to 3 pounds I think

pressure regulator  fixed problem

fuel tank was lower and 2 feet away from carb

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


  • Who's Online (See full list)

    • Skelsey1989
    • SmilinSam
    • TomSchmit
    • Sovereignm88
  • Today's Birthdays

    1. Mustangsvo
      Mustangsvo
      (37 years old)
    2. RenegadeJ
      RenegadeJ
      (82 years old)
    3. srwven
      srwven
      (50 years old)
  • Recent Status Updates

    • Paul M.Murphy

      Paul M.Murphy

      Hello glad I got on this site. I hope to upload a couple of photos of my Simplicity Broadmoor 
      Model 707 Tractor. I have replaced all the belts on it and installed a new ignition switch.
      Have a mower deck which was in poor shape , repaced a couple of bushings and welded the
      deck where there was some holes. The tractor and mower deck came from a friend and the 
      mower deck metal was getting pretty thin. Some new metal was put in it and we also undercoated the underside of the deck. This was done by my friend Greg Toulman.
      I have not put the mower deck on the tractor yet, waiting for Greg to come home and give me a hand. Can you please tell me if there is a manual for the mower deck and where I could get one.
      I would also like to get some moon wheel discs as well.
      I will try and down load some photos of the tractor when my wife shows me how to. 
      I really love driving this tractor and also how well it is made compare today's tractors, especially the flexible rear end and the rollers.
      Tell the next time 
      Paul
       
      · 9 replies
    • jbrooks

      jbrooks  »  Talntedmrgreen

      Josh
       
      folowing  this from a link at the downloads.  I just rescued an AC 920 with the lambodini diesel. I can' t download  yet .  Where did you find the PDF copy you posted. . I would like to figure out how to adjust the injection pump. 
      I assume it's a bosche, correct
      · 0 replies
  • Adverts

×