Cold starting issues - new build rover 3.5v8

atkinsal · Post by **atkinsal** » Mon Nov 06, 2017 9:58 am

Hi all

Wonder if anyone can help.

I have a series 2a landy which I recently fitted with a rebuild rover 3.5 v8 from a Rangie classic (been wanting to do it for years!!). As part of the rebuild I also replaced the igntioin electrics with a kit from powerspark so it has new distributor, 8mm leads, plugs, coil etc.
We also rebuilt the carbs (strombergs CD175) with new gaskets and it also runs on lpg.

So the problem is that it starts and runs well when it's warm but is an absolute bugger to start when the outside air temp is cold. In the summer it was ok, I could get it to start but now it is getting cold it is an ordeal to get going. I usually crank and crank and then smell petrol in the exhaust so give up. When I come back in a few hours (and often with jump leads) it will eventually fire but again, after cranking and cranking. Once it fires just once it will then restarts straight way, even if I turn it off as soon as it starts the first time.

Also I’ve never been able to start it on lpg when the engine is cold, even in the summer. Again, it'll start on lpg after the engine has been fired up the first time.

So, anybody have any ideas that might help. I've never owned a rover v8 so am at a bit of a loss where to start troubleshooting.

Is there a technique to starting these v8s when the air temp is cold?

I thought I might be over choking but have tried without and, a little and a lot, still doesn't seem to help.
I did think perhaps I'm not getting a really strong spark?
Any pointers on how to diagnose the problem would be great.

Thanks. Alex

Specs:
Rebuilt (with Rimmer kit) 3.5 v8 from late 70s / early 80s range rover
Carbs - strombergs CD175
Complete 35DLM8 Electronic distributor
Genuine Lucas ignition module
Genuine Lucas DLB198 Coil
POWERSPARK™ 8 Cylinder Red Powercor HT Leads 8mmmm

DaveEFI · Post by **DaveEFI** » Mon Nov 06, 2017 10:59 am

I'm a bit confused here. Is the dizzy Powerspark or genuine Lucas?

The Lucas DLM has simply a VR sensor inside it with the amp on the outside doing all the electronics. It is a very good system, except where the amp gets overheated. Later versions moved the amp to somewhere cooler.

I've had no direct experience of them, but read lots of bad comments about some Lucas copies. And seen a dizzy which was very badly made.

ChrisJC · Post by **ChrisJC** » Mon Nov 06, 2017 8:57 pm

The fact that it is unsatisfactory on both petrol and LPG suggests it may well not be a fuelling problem.
Certainly my old engine would start on Petrol or LPG from cold easily.

Is the compression good?

And is the spark definitely good?

You could try cranking it in the dark to see if it is tracking from the ignition system somewhere.

Chris.

Ian Anderson · Post by **Ian Anderson** » Tue Nov 07, 2017 6:36 am

No bypass circuit to feed 12v to coil direct when cranking instead of through ballast resistor?

Ian

garrycol · Post by **garrycol** » Tue Nov 07, 2017 6:59 am

I had the seem issue as the OP on my 3.5 on gas and petrol. I never did resolve it and in the end I ran a tube from the cabin to the inlet manifold and when the engine would not start a squirt of "Start Ya Bastard" starting fluid into the tube got it going.

In investigating - there was no problem with ignition. Ensuring the carb dash pots were full of the correct grade oil helped. Full choke on and no accelerator for starts. Running the fuel pump for a while before start helped. If the engine did flood, choke off - accelerator to the floor, fuel pump off (and I have a spot between lpg and petrol where the fuel pump is off) and crank until clear - often would start.

If running on LPG, when parking up for the night or a long period in the cold I would switch over to petrol so the carbs would be full of fuel for the start next morning. A squirt of LPG from the gas primer button would often start the engine on petrol.

However despite a lot of looking I never solved the problem - started always in summer but was very problematic in winter. The squirt of starting fluid into the tube via a tyre valve stem worked.

One of the reasons I am changing the engine out for an injected version,

Garry

DaveEFI · Post by **DaveEFI** » Tue Nov 07, 2017 9:27 am

Ian Anderson wrote:No bypass circuit to feed 12v to coil direct when cranking instead of through ballast resistor?

Ian

Not used with the DLM dizzy.

Ian Anderson · Post by **Ian Anderson** » Tue Nov 07, 2017 6:01 pm

DaveEFI wrote:
Ian Anderson wrote:No bypass circuit to feed 12v to coil direct when cranking instead of through ballast resistor?

Ian
Not used with the DLM dizzy.

But is there still one in the circuit?

A wire with two crocodile clips to jump full 12 volt to coil will prove it very quickly one way or the other

Ian