Hi All, Sorry for the long rant BUT,,
I was asked a couple of months ago if I would surprise someones Grandfather for their birthday who used to own a Mk2 and always regretted selling it. I thought it would make his day so said yes and today was the day. So this morning I started her up and she was missing slightly so popped the bonnet and there was a small amount of water sitting around plugs 3,5 and 6, no idea how it got there as it has been sitting in the garage, so will have to keep my eye on that, but turned her off soaked up the water and decided to check the plugs to make sure all Ok. Well 5 and 6 came out ok but 3 felt like it was cross threaded but eventually it came out and almost brought the Helicoil out with it. Managed to get it back in Ok but will have to do something more about this latter on, then went out and did my good deed.
The car run fine but when reversing back into the garage I notice fuel on the floor, I think it is coming from the Auxilliary Carb but while I was checking this out I went to start the car again and it just clicked then nothing, not even trying to turn over on a week old battery so am now thinking the starter motor has gone, add all this onto the fact that It is a newly built engine with less than 2000 miles on it and I'm sure you can all feel my pain. Thing is I don't really have much confidence with the firm that did the rebuild so expect I will end up going elsewhere but need to think about my options first but I need to get her started. So after deciding that whoever's in charge upstairs hates me I have come inside to sulk. Is the starter motor a straight forward swap or am I going to loose yet more skin off my knuckles ?
Thanks guys.

 

The fuel on the floor is most likely from a stuck or sunk float. If it were not that the aux could not overflow. Before you decide on the starter check the starter relay which has a manual button on the end--make sure you are out of gear!

 

Tried the starter relay and the same thing happens,,, not a lot. Did I read your message correct and the aux can not overflow ? Next to mine are three long (about 75mm) cylindrical tubes about 5mm in diameter and the two outer ones are full of fuel......this can't be right can it ??

 

Sounds like the floats are stuck down. Take the tops off the bowls and see where the floats are.

 

I'll check today but nothing coming out of the overflow tubes.

 

a1lry, pics are so much easier than a description if possible. I can't figure what/where these tubes are.

Re starter motor, put the car in gear, and rock it back and forth a couple of times, this is just in case the Bendix gear has jammed up on the starter ring, (unlikely but possible), also try tapping the started motor with a hammer, a solid tap not just a tiny tap but not a full on whack either, then try pressing the solenoid again. Sometimes if the brushes are worn or sticking this can free them up, but if they are worn they will need replacing.

The click is generally the solenoid, but if you are manually pressing the solenoid, you should not hear a click as the motor does not have a relay/solenoid internally, it is simply a motor. If you hear a click and whirring, then the motor is spinning but the bendix gear is not engaging, but the click would be the bendix trying to throw out. This can be a dirty bendix gear shaft, but would require removing the starter to check/clean.

To remove the starter, there are 3 bolts, 2 of these are joined together with a loop of steel bar for ease of working. You will have to remove the center console, there is a round access plate near the front on the drivers side, you have to access 1 of the bolts through this hole, unless you are very dexterous.

Post pics of the tubes and let us know where you get with the starter.

 

Have tried rocking the car but no different. Going to give it a clout today and see but is only 6 months old maximum. Was all replaced when the engine was done like I said but don't fancy returning it back to to garage to rectify as found several things that are not just wrong but bad practice I think. I have attached a picture of the chambers next to the Aux carb that are full of fuel, I have checked them today and the level is slowing dropping.

 

Hear is a picture showing the position better.

 

You are referring to the holes to the right of the slotted screws in the picture which appear to be full of liquid (fuel) ?

This is the intake passage and should not be full of fuel.

Take a look at this Auxiliary Enrichment (Thermo) Carburetter - SU Carburetters you will see the fuel level line, this should not have fuel in it above the fuel line especially when the ignition is off (should be impossible with ignition off)

Turn the ignition on for 30 seconds to fill the float chambers, then use a tissue to soak this up, then check if it refills, do not turn ignition on, also check the float level and float position(is it submerged or floating).

Does the fuel level line up with that on the SU Carb diagram ?

The auxiliary carb should not draw any fuel without a vacuum from the inlet manifold AND the aux carb on. It is possible to fit the fuel passage (Part16 on diagram) upside down, but you should have had problems before now, and it doesn't look like that's the case looking at the pictures, but the fuel level in the intake passage would be correct if it was upside down !

If we rule some stuff out we can try and diagnose the leak.

Let us know re starter.

 

Thanks TilleyJon, Will take a look at this and let you know. Have attached a picture from the underside of the Aux carb and it shows where fuel has leaked out.

 

There appears to be a leak around the aux carb solenoid base, lift off the solenoid and see if there is fuel there.

There should be no fuel at that point only when mixed with air and pulled up by vacuum.

If there is fuel there we need to find out why as that will be the issue, can you post a shot showing the connection to the carb as well as the enrichment carb, same angle as the pic above but a wider view.

 

One more try at this---your carbs need access to air (floats). If there is damage to the overflow tubes, or the special washer is installed on top rather the bottom, or critters have clogged the vent tubes you will have overflow. That overflow will go to the AUX carb or to the carbs themselves which will drain via the drain tubes connected to the connecting manifold for the air cleaner (do you have drain tubes there?) . HOWEVER the very first place to go is the floats for the carbs! They could either be mis adjusted or sunk either fully or are partially full. While you are checking pay attention to the special slotted washer for the float bowl vent tube. It should go on first--then the tube then the solid (normally alum) washer and carb tag.

 

One other comment. from the pics there has obviously been very extensive rebuild work in this area (lots of plating and polishing). How many actual miles do you have on this rebuild effort?

 

Thanks for the info George, won't get a chance to check over the floats until next weekend now. She has only done about 2000 miles since a full rebuild, the garage is supposed to of fully tuned the car on a rolling road ,which I know it has been on, but when we checked afterwards the jets where at different heights, asked them to check the float height as well but don't think they did.

 

What kind of float valves were used ?

XK's unlimited have Grose valves with two ball bearings, I found that these can stick shut.

Other types use a conical neoprene tip that works well when new, but becomes slightly swollen and softish.
When this happens, the softened tip binds on its sealing surface and it can leak.

I found a bronze/brass conical tip works the best.

Also, how's the oil level in the damper tubes ?
A situation that I experienced was flooding when there was no oil in the tubes.
With no oil in the tubes, the pistons rise far too quickly on acceleration and allow a huge gulp of fuel into the engine.
This also causes a sudden drop in the float bowls and the fuel pump quickly compensates when the valves open up all the way.
The sudden rush of fuel can flood the starter carburetor as in your photo.

 

Jeff - George - a1lry
I thought we had ruled out float as A1lry has said in post #7 that he checked them and the level was slowly dropping, so I was assuming that something else odd was going on.

However I had listed a sort of checklist to check all issues from scratch hoping that ailry could eliminate certain things and get to a diagnosis.

 

Tilly as I read what he wrote it was clear to me he was only looking at the chambers on the aux carb. On his starter I am now wondering about that water on the head. Hope he does not have a leaking head gasket and hydrostatic lock.

 

Thanks to all for the feedback.
The oil in the damper tubes is good thanks George.
The guy from SU said that the fuel issue with the carbs could only be the Iron core plunger in the solenoid not seating properly and letting fuel through, either a Otter switch malfunction ( which I don't have ) or a small bit of sh@t or something fouling it. If it keeps doing it they have all the spare parts available if needed but due to the age of the carbs the seals etc should be fine so would recommend keeping an eye on it for now. After I soaked up the fuel in the intake passage it has been fine, even managed to start the car after giving the starter motor a stern talking too with the club hammer. As for the water issue I am not losing anything from the rad and no signs in the oil either another thing for me to keep an eye on.

 

Well at least you have it started, better carry the stern talking tool in the car in case it needs a further chat with the starter.

If it does need further talking to, I would suspect worn / carbon clogged brushes, or sticky Bendix gear, they are usually the culprits if the starter needs telling off !

I'm not convinced that the guy at SU is correct re the seat, there should not be enough fuel at that point to cause a leak, otherwise it would leak whenever the choke is on !
But as you say, keep and eye and come back if you get further problems.

Jon

 

The starter is only 6 months old but has no markings so don't know which brand it is until I get it off this weekend but have a new one coming tomorrow. I don't want something that is not doing its job, I may punish it again when I take it off just to let it know who is in charge.....
Regarding the carbs, if something is not your forte you have to go with someone who is supposed to know what they are talking about but over the last 12 months I have been feed a lot of old flannel and bullsh@t by these so called experts so will keep you informed.... watch this space.