5 replies to this topic

[minicyp]

Model: Classic Mini saloon, 1275 (believed A+, engine number plate missing)

Year: Pre-1982 (pre-Verto clutch)

 

Photo of the engine bay attached, apologies for the state of the wiring, tidying it is on the list.

 

Spec as far as I can establish: SU HIF38 (plate reads FZX1414), Lucas 65DM4 electronic distributor (42664 / AUU1536) with 84896A amplifier module, negative earth, alternator, no ballast. Two open breathers, one each side. Standard cast exhaust manifold as far as I can tell. I can't confirm engine capacity, no engine number, no plate, and I haven't found casting numbers yet. Don't know what needle is in the carb either.

 

Description of problem:

 

Started as a fuel tank replacement and has turned into a long job. Here's everything that's been done, in case any of it is relevant.

 

Fuel system (all new): New 7.5 gal tank with sender and seals, all new 5/16" injection-rated hose throughout, GSS154A vented locking cap. Electric pump (New-Era NFP-100J2) mounted under the tank. Malpassi Filter King FPR006 regulator between pump and carb. No pre-filter before the pump at the moment.

 

Electrical: Found the engine-to-body strap getting extremely hot when cranking. Cleaned the earth point back to bare metal and replaced both the strap and the negative battery lead. Cranking is now strong and the strap stays cool.

 

Ignition: Original coil was a Lucas DLB105 (3 ohm), which I now understand is wrong for a 65DM4. Have since fitted a GCL143 and the spark improved. Plugs are new NGK BP6ES, gapped at 0.9mm. The distributor has not been removed or disturbed at any point.

 

Carb: The jet was seized solid and wouldn't respond to the mixture screw at all. Freed it with repeated carb cleaner soaking after taking the carb off — it moves properly now. Dashpot refilled.

 

The oil incident: While running it on Easy Start it violently ejected oil across the whole engine bay; both headlights, the radiator, the distributor. I shut it down immediately. Drained the sump and got roughly 10 litres out where it should hold 4.5, and about half of it was petrol. That was weeks of cranking a badly flooding carb washing fuel past the rings. Cleaned both breather canisters, sealed the dipstick (there was no seal on it at all), refilled with fresh oil. Level has been stable since and no leaks.

 

Fuel pressure: I'd been guessing at the Filter King setting with no gauge, which is what caused the flooding in the first place. Have now fitted a Sytec 0-15psi gauge to the regulator's outlet port and set it to a steady 2 psi.

 

Where I am now:

 

After fitting the GCL143 it fired up and ran for about two minutes, then died. I kept trying to restart it and cleaned the plugs a few times before realising the tank was empty. Refuelled properly.

 

Now it won't fire at all. Confirmed:

- Strong, sustained cranking

- Spark present

- Fuel pressure steady at 2 psi on the gauge

- Clean dry plugs

- Fuel mist at the carb mouth (air filter currently off)

 

What's puzzling me is that Easy Start doesn't work either. It fired readily on Easy Start several times earlier in this process. Now nothing at all.

 

Questions:

 

1. Why would Easy Start not fire it when it did before? That points away from the carb to me, given I have spark and strong cranking.

2. Should I be suspecting the float needle valve? Before it ran out of fuel, the pattern was that it would run on the fuel already in the float chamber with the pump disconnected, but flood as soon as the pump was connected.

3. Any way to identify engine capacity without pulling the head? Happy to clean the block and photograph casting numbers if someone can tell me where to look.

 

There's also a minor coolant weep at the head-to-block seam which has been there a while, but I've not looked at it yet.

 

Any pointers appreciated. Happy to post more photos of anything useful.

[Quinlan minor]

Compression tester time.

[colinf1]

It sounds the same as my previous problem, head gasket gone between two cylinders, so no compression.

As there's already a weep present, might be time to take head off and inspect....

[lsto]

Generally if it has 2 crankcase breathers fitted it's a 1275. This photo looks like an a+ to me. Check if it has tappet chest covers. If it does it's a small bore, if not it's a 1275.
It's hard to tell but it looks like the breather port on your carb is open, if so block it off as it will be causing a massive air leak which may be your problem.

Edited by lsto, Today, 09:42 PM.

[lsto]

I think this is your breather port, block it off and try again. Ideally it should be piped up to your crankcase breathers.
Good luck

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[Earwax]

Hi   

 

Just a couple of checks you may as well try   as well as compression test     

 

Re Hif38 hoses   .... have you got your float overflow connecting to the crankcase breather return?   (possible overfuelling) 

 

 I would 'start' with float overflow tubed down to the ground ( just to avoid petrol hitting hot engine) and I would cap the Crankcase breather   See Calver ST as example  here 

 

I would also verify at the carb inlet that fuel is pumping ( pop it off for a second whilst someone turns fuel pump on / cranks) ... I do like the Malpassi filter king but I have seen weird sorts of float bowl full to float bowl empty type behaviours which have stopped after temporarily bypassing the filter.

 

I would also leave the fuel cap off to see if it makes a difference ( venting not working and builds pressure against the pump)

 

I would throw a different set of plugs at it after you are sure no overfueling is occurring.

 

 

On another To Do list ( you may or may not get around to ) It appears as if the engine has been strap lifted - dents in front hard oil pipe and rear carb warming tube - just FYI really