Suggestions please !

[sidevalve44]

Suggestions please. I finally finished putting my 1960 Briggs & Stratton model 80331 3HP together. After several pulls it finally burst into life, but cut out after a second or so. Several attempts were made after this with the choke on and off and each time the same; burst into life but cut after a second or so. There is no throttle setting, it powers a pump so, the throttle is set flat out and should adjust itself on the governor. Both screws on the carb are set about 1.1/2 to 2 turns out. There seemed to be a lot of petrol in the carb body beneath the airfilter so, could it be flooding ? A few pointers would be appreciated before I rush in and start taking things apart again.

[vhgmcbuddy]

hi, maybe a diafram issue?????

[hillsider]

Hello Kevin,
There are a few things that could cause your problem, it would be helpful if you could post the Model, Type and Code numbers for the engine then we can look up the correct manual for your engine and can hopefully give you better advice.

Ray.

[sidevalve44]

Thanks for replies.

No Diaphragm in this carb I’m afraid. It’s a float and needle type.

Engine Model 80331, Type 943393, Code 6004250.

Unfortunately, the unit was a non-runner when I got it so I have no previous settings I could fall back on.

I stripped the carb and found previous owner had re-assembled badly so re-built accordingly. I suspect the float height maybe too high but, it could of course be something entirely different. The coil, points and plug etc., are all new.

Robert.

[joegrgraham]

Hi Robert,
It looks like you’ve got the briggs flo-jet carb on there.
I had very similar problems with my briggs engined Trusty.
The flo-jet is a good carb when it is all new and shiny, but they become very temperamental when they are a bit worn.
I suggest you strip the carb, check the float height, it should sit parallel with the top, and then treat it to new needles etc. The kits are available from the US on a certain auction site for not too much money.
Also, check the fuel flow to the carb, may be a bit of a blockage somewhere.

Hope this helps,

Joe

[hillsider]

In addition to Joe’s suggestion you are probably aware that the emulsion tube needs to be removed before you can seperate the float chamber away from the upper body. Be carefull before assemby to ensure that all passageways are clear and set the ide and main mixture screws to a base position of one and a half turns open from the lightly closed position.
This shuld allw the engne run and fna adjustment can be made when at operating temperature
Ray.

[wristpin]

That carb is officially known as the Two Piece Flow Jet and came in three sizes.
Even when new and unmolested they could be a B****** and fuel pooling in the throat is quite common.
On my Landmaster cultivator more than one pull on choke is asking for trouble!
If you Google Briggs Two Piece ….etc there’s a lot of useful stuff but beware of uninformed diy Youtube stuff!!

These could be useful
http://outdoorpowerinfo.com/repairs/briggs_medium_two_piece.asp

On older carbs two things to watch out for are – warped flanges between top and bottom halves – often the result of over tightened screws – allowing air leaks.
Internal leaks where the emulsion tube or nozzle screws into the carb , again possibly due to over tightening or corrosion between the brass nozzle and alloy body. The fixes for this include using a modified spare nozzle to carefully lap the seat or using the teflon washer from a Vacu or Pulsa Jet repair kit on the tip of the nozzle to seal it.(Pt No 391413)

This link to the now defunct PER forum explains the repair process
http://www.perr.com/tip9.html
Just glad that I don’t see the small, medium and large Two Piece Flo Jets much now!!!

[will-haggle]

Neither of my machines have run satisfactorily since last October. I’ve got my 1968 Merry Tiller running fairly well now, still hunts a bit even with a different carb. and governor spring, I’m just stripping the carb. on my 1965 model now. I’ve found debris in the tap, tank and fuel pipe so far, pushed an old throttle cable through the pipe, got the tap off and cleaned that out, debris visible in the connection on the carb. body. I have found that if you are very careful you can avoid damage to the emulsion tube by removing the four screws and sliding the float chamber diagonally. They don’t unscrew very well anyway. Thanks Wristoin for you’re timely advice! 😉

[sidevalve44]

Thanks guys, there are some useful tips here. The link from Wristpin is especially informative.

Looks like I will definitely have to strip the carb again and pay especial attention to the float height and replace the emulsion tube. A previous owner had bent it (guess how !), I straightened it as best I could but it looks like I should replace it, although replacement cost in the UK is a bit on the high side.

All good fun !

[dave]

Have you considered ultrasonic cleaning of the carb? I purchased
an ultrasonic cleaner from Machine Mart last year and I have
cleaned the carbs on my Ransomes and Roberts Trusty in it and
both machines seem to be behaving a lot better since a good
vibratory clean.

[wristpin]

The U/S tank is certainly a useful addition to the carb cleaning armoury. When I had the business we were an early adopter of U/S cleaning and I believe can take the credit for introducing it to Briggs UK.
If anyone is considering buying one I would advise going for one with a heater and if using a basket for the parts a stainless steel mesh one absorbs less (8%)ultrasonic energy than the plastic equivalent (30%). That info came in the instruction book for my present 3ltr domestic tank which came with a plastic basket but when I enquired about a stainless one the suppliers said none available! Struck me as a bit odd. Anyway I found a suitable ss one in a cookware shop!
A useful tip that I was given is that when cleaning carbs, split the cleaning time into two or three and alter the orientation of the carb in the tank between sessions – helps shake the loosened crud out of any blind drillings etc.
When I was learning the trade “way back when” we were always told not to poke bits of wire etc through blocked jets and you can still see this repeated in older workshop manuals. However, four or five years ago when Honda were having horendous carb issues with the Vee twins fitted to Coutaxes and Westwoods etc they came up with a “Dr Carb” cleaning procedure and together with the detailed instructions came a pack of wire probes!

[andyfrost]

Angus , thanks for that , I’m considering one. What solution do you use / recommend ??

Thanks Andy.

[wristpin]

Some people just use a couple of drops of washing up liquid, on American sites there is quite a following for Seaclean which I believe is available over here . We used to use Ultrawave, Ultraclean SA in the tank at work and I have continued to use it.

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[charlie]

Whatever additive you use make sure it is safe for the type of metal that is being cleaned. Some will eat aluminium!!!!

[hillsider]

http://www.maplin.co.uk/p/jpl-seaclean-2-double-strength-concentrate-05l-a76lg

I use the the Seaclean product available from either the company in the above link or via the internet in my U/S cleaner and it works fine. The issue of cost over capacity is a major deciding factor with these machines, I settled on the 2.5Ltr heated machine from Maplin and have been pleased with it so far.

Angus, were you thinking of this product
http://www.tractorsupply.com/en/store/sea-foamreg%3B-motor-treatment-for-gas-and-diesel-engines-16-oz.
It seems to be used as a cure all for most problems over here, but the last time I looked it was quite dear in the UK if you can find it!

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