Water leak

[Austin Nippy]

Hello again,
I've just had a quick run for about 5 miles. It seems slightly better on the flat having oiled the carburettor last night (there isn't an oiling hole on the dash pot Stuart. However a local country lane with a slight incline we used to romp up at about 45 in the past was quickly 3rd then 2nd gear and struggling over at under 20. 
There is certainly petrol getting through to the carburettor Malcolm but thanks for the check. As you say, it certainly used to run very well from what we both understand so I'm at a loss as to what is wrong here as nothing has changed on the engine since I bought it last year. It's just been sat waiting to go in the car when I got a bit of time. I would guess that after about 50 miles now it should have cleared any spiders and fluff out?
The mystery continues but, after tomorrow afternoon, I'll have no time to do anything further for the foreseeable future unfortunately.

On another note, the gears seemed slightly less whiny - maybe they're bedding in a bit or perhaps I'm just getting used to them now...

Best wishes,
Nick

[Austin Nippy]

Hello yet again,
This is a bit of a random thought but the only thing which has tangibly changed on the engine since I bought it is the distibutor. The "new" engine came with no distributor included so I've put on the distributor from the old engine.
Whilst this seemed to work perfectly well on the other engine, is it possible that it isn't as good as I thought it was? It has done something approaching a starship mileage without apparent issues. It now has new points, rotor arm and condenser and gives a good spark, could it be that the auto advance is less than perfect?
I timed the engine on number 1 which is obviously about right to start the engine. If I advance it more than a few degrees the starter struggles to turn the engine over. Is it therefore not advancing properly once under load which would produce the gutless acceleration and hill climbing abilities we're experiencing?
If that makes sense, does anyone have a proven good Lucas DK4 distributor either for sale or one that they're happy to loan to prove / disprove this train of thought?
If that should prove to be the issue, does anyone know who can refurbish a DK4 so that it works perfectly?
Maybe what looks like a petrol issue is, once again, ignition related...
Best wishes,
Nick

[Tony Griffiths]

Nick, about the whine from the straight-cut gears. Here's a quote from David Wortley a few years ago about the Super Accessories close-ratio set he fitted to his Ulster: "I have had a Super Accessories 4-speed box in my all-alloy pretend Ulster for the last 25 years. I live in Sheffield and use the car in the Peak District, and I find that 3rd gear is too high around these parts. OK for overtaking on the flat roads, but a lower 3rd would be better. Makes a very nice whine in the intermediate gears." I have the car now, and I've never been concerned about the whine - it just sounds lovely - very 'racey'. The car runs a 5.125 rear axle and goes very well indeed; it climbs the long hill up past the Chequers Pub towards Sheffield in top gear, a road that has my standard 1930 Chummy down to second in places.. I find that third in the Ulster is OK in Derbyshire; perhaps the last engine that David built for is more powerful.

[Malcolm Parker]

I've been having a few distributor problems of late.  I would try an earlier manual advance retard distributor (Lucas DJ4) on the car.  They are ridiculously simple and don't have the tendency to develop shorts like the later Ruby type.
I am sure that your problem is ignition related.

[Austin Nippy]

Hi Tony,
Thanks for the encouraging words about the gears - the noise was certainly a surprise to say the least. I guess it depends on how noisy is noisy?...
My car is on the 5.625 Nippy back axle so a little lower ratio than your car so the higher 3rd will hopefully be fine. I was recommended these gears as being superior to the standard Nippy ratios so followed the advice.
The bigger issue is that my car simply isn't going at all well and, as I've mentioned previously, any slight incline is quickly down to 2nd and a slow slog over it. My other engine, prior to making nasty noises towards the back end of last year, has always gone extremely well - comfortable cruise all day at 55 and climb anything with ease. I was expecting this engine to be at least as good but, so far, something is amiss and I don't really know what to try next. 
Hopefully somebody will know how to sort it?
Best wishes,
Nick

[John Cornforth]

Hi again Nick

If you look inside a DK4A, or even dismantle it, everything can often look OK. However, the nature of its design means that even small amounts of wear can have a profound effect on the advance curve.

If you want to know what the advance is doing, I recommend fixing a pointer next to the camshaft pulley and placing a TDC mark on its rim. Then check the timing with a cheap Xenon strobe light as you rev up from idling.

Ordinary A7 engines don't seem to be too critical on ignition advance. The earliest with manual adjust types more or less used two settings, slightly retarded for hand starting and 20 degrees advanced for everything else (I'm exaggerating, but not by much). Later auto-advance types used typically 4 degrees static advance and 16 degrees centrifugal, giving a total of 20 degrees. The centrifugal "curve" is close to a straight line because the two springs are the same. It then hits a top limit at about 2000 RPM. The top limit is set by pegs touching the sides of small holes in the action plate.

A sportier engine won't necessarily need any more advance. The spark plug is fairly central, the bores are small and a high compression head generates plenty of turbulence. Modern fuel can have a shorter burn time. The only way to tell is by experiment.

One thing you could try is to get the engine warm and running, then add another 5 degrees crank advance (move distributor body by 2.5 degrees which isn't much) and see if and how the hill climbing changes.

As for overhaul, the "Distributor Doctor" (Martin Jay) would be a good place to start. For a non-standard engine he will need to know what advance "curve" you need.

[Austin Nippy]

Hi John,
Thanks for your suggestions. What would I be looking for regarding the timing check with a stobe please and how would I find it? I don't have one having always set things up "near enough" on number 1 to get things running and then fiddled with the distributor movement to find a sweet spot.
I'll try the "warm it up and advance it a bit" method and see what happens. I guess though that this means I'd have to manually retard it again to start next time it as any further advancing the distributor by turning it means it's too far for the starter to turn the engine.
I've no idea about what advance curve may or may not be needed I'm afraid so that probably won't help the Distributor Doctor.
Best wishes,
Nick

[Ruairidh Dunford]

Are you able to ask Paul about the grind on the camshaft?

Some are profiled for flat out racing, these work extremely well at high revs but are almost un drivable on the road.

Several cars have come to me with this issue, a cam change has resulted in very positive results.

[Austin Nippy]

Good evening again everyone and thanks for the replies.
I'll try my best to answer the points made..

I don't have a DJ4 distributor to try unfortunately Malcolm. I have found another DK4 in a box of bits but have no idea of its provenance or functionality so it seems a bit pointless (no pun intended!) trying that until the car is running properly as it could just add to the mystery I suspect.

Do you have a contact number for Paul Bonewell at all Ruaridh please? I've no idea what he did to the camshaft as it was in the engine as bought last year. All I know, from what I've been told, is that it is an extremely fast engine and the gentleman who sold it to me last year found it was too quick for him to drive as it accelerated strongly from about 4000 RPM. I beleive the tappet settings are not all the same and differ somewhat from a standard engine. Somewhere there's a piece of paper with all sorts of myserious numbers on. Whether Paul would remember this specific engine or not I don't know as it's possibly quite a while since he did whatever he did to it. I guess it's worth a try though.

Since my previous post, I've managed to improve it slightly although this may be a(nother) red herring. The choke wasn't fully retracting on the SU. Having lashed it wide open with a piece of wire (ie no choke in operation) I managed to get up the slight slope to the M! near my home in 3rd gear at about 40. It wouldn't pull top and accelerate but it's beter than struggling up in 2nd like the other day. I've fiddled around a bit with the mixture nut but this doesn't seem to have made any difference at all so it's now back where it started off. Should there be some sort of spring to pull the choke back once it's no longer needed at all or is it just a manual push back?

There was also a smear of petrol around the bolts holding the carburettor to the manifold possibly due to a lack of a gasket at that joint. I've put a gasket on with some goo and will see if this has made any differece once it's set when I get chance. There wasn't an obvious induction leak but you never know...

The only other thing which may be worth swapping is the coil as this has been on the car since I bought it in 1991 and, I suspect,for a long time before that. It seems to give a good spark but maybe it's finally on its way out. Is this worth a try anyway?

Hopefully at some point we'll be back up and running but just not sure when now.

Best wishes,
Nick

[Malcolm Parker]

I wouldn't worry about the cam, I've been in the Type 65 with that engine and it was very driveable.   Paul Bonewell supplied the camshaft knowing that it was going into a road car.   For the carburettor, I would set the jet level with the bridge and lower the jet by eight flats of the hexagonal brass adjustment nut, that is a good starting point.   The choke lever should have a short spring to pull it closed, they simply hook on and can easily fall off.
I am pretty certain that your poor running is ignition related.