Suffolk Punch running issue on Qualcast Cultimatic.

[Wristpin 400]

Carburettor. The choke should stay put with friction supplied by a small compression spring and its position located by a pin moving between two cast "upstops" in the carb body.

Valve chest cover. May just be a perished gasket or the flange may have been distorted by over tightening. If the latter a squirt of sealant either side of a new gasket may sort it or even two gaskets .

If you carefully slacken the nut holding the exhaust box onto its manifold will allow you to swing it out of the way. Take time to work the nut loose as its not difficult to shear the threaded end of the manifold. If the worst happens you can drill and tap the end of the manifold to take a set screw.

Edit. Just got brain into gear! What you are seeing is possibly not a leak as such but oil vapour being expelled through the breather valve incorporated in the cover. Take the assembly off and give it a good wash in petrol . Don't go poking around in the flap valve as this may make things worse.If the valve is sticky this should help but if the valve is worn or the engine is worn and "breathing" there's no quick cure - just live with it!

Edited November 23, 2015 by Wristpin

[jonnym 9]

Thanks again, great info as usual.

The leak was quite large. The top plate was a wash with oil and I could see it coming out!

I will try resealing the gasket and see how I go.

The choke has the spring assembly with it and there is slight resistance, I wonder If I have a problem further up the carb forceing it, also as you can imagine as its on a rotovater it does jump around alot exasperating it.

Thanks again

Jon

Sent from my GT-N7105 using Tapatalk

Edited November 25, 2015 by jonnym

[Wristpin 400]

If the spring on yours is compressed  with a similar push on retainer you could try increasing the friction by gently tapping it toward the carb body - perhaps using a small socket as a driver. 

[jonnym 9]

Hello again.

 

I've got the rotavator out and once again its being a bugger.

 

It wouldn't start, so I checked for spark, all OK, it had a new plug last year used once.  I've stripped and cleaned the carb so I know the jets aren't blocked and put on a new gasket.  I positioned both jets to one turn out.

 

Still it won't start, but I did destroy the already ailing pull starter trying.   So off comes the head, none of the bolts were more than finger tight, except one which sheared.  The cylinder head gasket looks like it had seen better days and could have been leaking.  Inside all looks fine, no sticking valves, no scoring or damage to the piston liner.   So a quick decoke, new gasket, drill out the old bolt and all back together, with the addition of a new pull starter mechanism.   STILL WON'T START!!!  Now its just trying my patience.  So off comes the pull start and I adapt the broken one fit my drill. guess what....nothing it won't start.  Its just sat there like an over grown yellow paper weight.

 

Looking at the spark plug I don't think its getting fuel so before I order new jets, is there any thing I've missed (apart from hitting it with a large hammer)? 

 

Thanks again

 

Jonnym

 

Edited April 30, 2016 by jonnym

[C-101plowerpower 548]

is there petrol in the tank? if so how old is it? does it start on starting fluid?

[jonnym 9]

Petrol was fresh about a week ago as I always drain it all to over winter.  Easy start doesn't have any effect either.  I've just restripped the carb and its jets are not blocked.

There seems to be compression, turning by hand with out the plug in sucks my finger.  I'm baffled. 

 

jonnym

[C-101plowerpower 548]

maybe try another plug?

[jonnym 9]

Yes will try I think I have a spare somewhere.   Although I can see there looks to be spark.  If this doesn't work I will try pouring the rest of the fuel all over it and seeing if its fresh enough to catch fire

[C-101plowerpower 548]

outside the head the plug may spark but it might loose it under compression

[jonnym 9]

I'm at the Basil Faulty stage now and beating it with a branch

 

 

 

I put the lawn mower plug in the rotovator, after mowing the lawn and nothing.

 

I put the plug from the rotovator in the mower and it started first time.

 

What next.  I wonder if its spark isn't strong enough. although it gives me a belt when I hold the end of the cable and plug at the same time.

 

Jonnym

 

Edited May 1, 2016 by jonnym

[Wristpin 400]

So is it the act of swapping plugs that is creating / solving an issue? Dodgy plug cap or HT lead connection - either end?!

[jonnym 9]

No the plug swap didn't work.

 

This is my logic, The jets aren't blocked and its got fresh fuel, so even if the jets aren't set up it would try to start even if if it was just a couple of pops.

There appears to be compression although I don't have a gauge and there was nothing to indicate there wouldn't be when I had the head off.

The plug is working as I've swapped it for the one in the mower.

So its either no fuel or no spark.  I'm leaning towards spark as its not trying to start at all although like I said its definitely producing a spark and can give me a good shock.

I will try wrapping the whole of the HT lead I can get to in tape just to rule out it having a nick.

Whats the process for replacing the HT lead once all the cowels are off?

 

There is not a plug cap, its the open loop of copper type with no obvious fault,  but I will take a closer look at it tomorrow.  Would a meter be any help in diagnosing this? 

 

thanks for the help

 

Jonnym

Edited May 1, 2016 by jonnym
more info

[jonnym 9]

The other thing I meant to say is I'm working outside and its too light to see the quality/colour of the spark.  I can't see any obvious damage to the HT lead, but it is leaking as it sometimes shocks me when holding it, and it does have some travel in and out of hole leading to the coil .  Does any one know how the the HT lead attaches, is it bonded or screwed?  I was hoping to find a nick in the HT as at least then I could have soldered a new section to it.

 

thanks again
 

Jonnym

[jonnym 9]

I've just been tinkering again.  I've covered the HT lead completely in tape and checked the spark.  Its not strong at all, not a nice blue strike just a small yellow one.

 

Could be one of two things, the HT lead connection at the coil/magneto end or the fact its kept outside under cover and the damp, condensation has got into the coil causing it to have weak spark.  

 

What do you think?

 

Jonnym

 

Edited May 2, 2016 by jonnym

[DevonianRedneck 86]

corroded points would be my guess if you hav'nt already checked them

[Stormin 4,458]

Is the plug wet when removed after trying to start it a few times? If not no fuel getting through. I know you've tried Easy Start but you may have a stuck valve.

[jonnym 9]

I've had the head off and the valves are all fine, yes the plug gets wet.

 

I've just been out taking the fly wheel of and end of the crank shaft has shear while removing the bolt.  Looks like it had a large inclusion at the break point, I used almost no pressure, while undoing it.  So I'm going to use it for target practice.   Or fit a new engine.  

 

The fly wheel still won't budge, so fitting a new crank shaft might not be an option(just seen one on ebay).  I've been quite rough with it as well to get my own back, and still nothing.  I think its been left outside for a long period by the previous owner.  

 

Thanks

 

Jon

Edited May 8, 2016 by jonnym

[Stormin 4,458]

Shame!

[jonnym 9]

Wow what a day.

 

I forged forward determined to find the error.  The fly wheel won't come off, I swear this rotovator is cursed.  

 

I've tried my fly wheel remover on my slide hammer, which didn't work, so I used it as a normal fly wheel remover using the screw holes for the starter wheel(not sure what its called), and a bolt on end of the crank, I torqued it up really tight and kept giving it a good clout round the edge with a hide hammer.  Still nothing, short of getting my extension bar out and swinging off it I'm stumped.

 

I think that the starting issues could be to do with the timing being off and the woodruff key mangled up in it, although I can't believe that didn't give way to the brute force it was under.

 

I think I should give it up as a bad job.

 

Jonnym

[jonnym 9]

I got a new engine and going to order a new crank....this will not beat me!

 

jonnym

[Stormin 4,458]

That's what I like to hear. Good man.