Forgot about your Scottish stereo typing lol, I'm not tight with money just surviving.

Here's the Carb servicing kit for the DMTR which seems to be missing bits that exist in the DTML kit. I'm sure as you say it probably would have been fine but you can see there is a difference with the gasket..

DMTR..

DMTL..

I'm going to take the other carb off the car and take the modified bits like the throttle spring arm which had to be cut for the Polo. I can possibly take the pump injector off and any other bits that seem in better condition.

Thanks. Well that's weird - my spare DMTL gasket (from Webcon kit part 9214140501) looks like your DMTR.

Scanner pic with 50p in case anyone wants to trace it onto oil-paper/cornflakes packet.

I'm sure it was supplied by fastroadcars, there's a note from Anthony in the box.

Didn't get those tiny circlips though.

I think the 2 large extra holes and 4 extra small holes in the DMTL gasket you have would all line up over the well (float chamber) which is at atmospheric pressure anyway - unless turbocharged!

^Yes in hindsight the DMTL kit might well have been fine and had extra bits but no harm

So the old carb came off and bits were taken off it for the new carb like the throttle spring arm and other bits that seemed in better condition..

Like any job there are issues..

1. I really don't know what the float height should be, The original carb seems to have a higher float height (1st pic) than the new carb? (2nd pic) Don't know the proper height because it doesn't relate to DMTR literature I have.

2. The plastic block that the carb sits on does not have a replacement item in this particular kit so I've got to use the original and its gasket surface is pretty messed up. I've drawn round it for a new gasket but how the hell do I get the old surface cleaned off without damaging it?

3. The original throttle spring arm that I had to modify has at some point hit the bulkhead and bent it (didn't modify it enough)Just shows how much the engine lurches back when you hit the gas! It's going to have to be straightened out because it is interfering with the choke spring but still have enough clearance away from the bulkhead. (modified one is the nearest)..

So without a car I was forced to take my carb home for assembly on the train..

Edited 27 March, 201016 yr by MacColl

DMTR FLoat height with gasket 7mm + or - 0.25 mm

gasket block - fill with bodywork filler then sand?

or lots of blue hylomar instant gasket. wipe any excess away when squash down before fitting.

If reaaaally bad

fastroadcars sell that block less than £7

I'm well confused now according to the lancia DMTR info I have the gap should be 6-7mm hanging vertically with the arm just touching the needle valve (the ball bearing). Is this right? It's seems like there is little movement, is it meant to be like this , just a small tolerance to allow needle valve to be either open or closed?

Sorry just noticed you've answered in mid post, hot water has softened the blocks gaskets I'm more worried about the float height in relation to the needle valve.

Edited 27 March, 201016 yr by MacColl

think i set mine at 7mm with that carb vertical..did you need to ajust it much then?

Yes I've had to bend it quite a lot but I'm not sure how the flap for the needle valve should be set?

It says in the lancia guide for the DMTR that the floats should be as you and dvderlm say between 6.75 and 7.25mm off the upper body which as you see in my last pic is set. The trouble is that I'm not sure how the flap for the needle valve should be set in relation to that? it seems to have very little sweep on it, or is that the way it should be with the needle valves ball bearing just touching the flap?

I'm out of a car until I can figure this out, thankfully I'm on holiday from Uni and kind of expected complications.

Well thanks to Steve I got the floats set the the right height, basically with the needle valve engaged(pressing the ball-bearing) your looking at 7mm gap between the floats and upper body with gasket. The other adjustment is with the sweep of the floats which should just miss the base of the chamber.

So with choke engaged the carb instantly burst into life, no fuel leaks but after a few minutes problems. Basically once up to temp I could not get idle. The idle speed adjustment clearly works but when the choke is disengaged it just cuts out or at the very least is a very lumpy erratic idle and it's at too high revs. The idle mixture however doesn't seem to do anything even when it is screwed fully in and when removed you can feel the draw of air on your finger. Does this indicate major air leak on the base or something else? hopefully there isn't something more serious going on.

I ran out of time , couldn't make any more engine noise in the workshop. Tomorrow I'll go to town with blue hylomar otherwise I'll maybe need to get a new base plate from fast road. Might try and get some sort of spray gasket if it exists?

does sort of suggest a big air leak

id prob go for the new gasket...if you do use sealer let it set up for 10 mins before you assemble it

Yes and cheers again, I've got a new block with it's bonded surfaces on it's way. What swayed it was the fact that it reads with the item..

It should be fitted dry, with no sealants used!

I think an air leak on the base is generally the route of most issues for any carb.

Just praying I get it before friday. I'm scared to attempt my rear wheel bearings in case something else goes wrong. the weather is utterly grim for having no car :(

you all the gear to do the bearings? its pretty easy to swap em but you need a decent hammer and punch, and something steady like a decent vice to work on

Yes cheers, got all the gear and the facility to do them including a vice. Got loads of guides to hand to.

remember to recheck em after 50 miles or so , they always seem to go a bit slack with me

Well by tomorrow that will be a full week without a car :(

I got the block with it's bonded surfaces from fast road and fitted it but still the same! The idle mixture still does nothing indicating some sort of leakage somewhere??? So I gave up with the carb and have decided to clean up the original carb and fit the best bits to it. So basically I'm back to square one.

Theres either some sort of fault/corrrosion with the carb, still a leak on the base plate/adaptor or some sort of avenue of air on the carb I haven't discovered.

What I find the most annoying part is the family comments and general rolling of eyes.. " why did you mess with the carb in the first place" "why do you bother with these old cars" gggrrrr

Well tomorrow(today) is a day of reckoning, I completely stripped the original DMTR carb that I've had running on the car this time and just hope that it responds to adjustments. You can see in the pic (sorry poor quality) the fresh block with it's bonded gasket surfaces that is meant to be a dry fit to the adaptor plate..

Edited 3 April, 201016 yr by MacColl

Fitted the above carb, decided to put a bead of hylomar round the adaptor plate side of the block.

It fired up straight away and the idle mixture screw after a few minutes started working, thank f*ck.

Seems to sit better at idle with lower revs which I suppose is a sign of better efficiency. The throttle however needs attention seems to stick and fluctuate, hard to explain but it doesn't give a steady sweep of power. Might just be sticking, just need to have another look as the arm that holds the spring has been further altered to keep it away from the bulkhead.

Just pray I don't still have an air leak lol.

oh and I even got my rear bearings fitted :)

I'm going to tidy up this thread with better pics, if anyone needs advice with this type of twin choke carb then hit this thread and me or more likely my fellow club members can help.

Edited 3 April, 201016 yr by MacColl