Car suddenly unreliable starts bad and suddenly dies

PepijnWK

Active Member
#1
The Rover 3500 has a sd1/triumph tr8 injection engine with a lucas 35DE8 distributor and a blue bosch coil. The injection part is of and back to carbs . There is no ballast resistor installed nor the ballastwire is in place. coil gets hot.
I am suspecting the coil or the distributor. Did I fry it not using a ballast resistor so giving it 12 volts the whole time instead less (9volts?) Or did the coil fail in such situation?
What can i do solve this?
I was thinking of buying a lumenition kit. but does anybody know what to buy without ballast resistor? Or should a buy a ballast resistor? could that be the main cause?

thanks for your answers!!
 
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#5
If it starts and runs I'd be thinking your issue is probably fuel rather than spark. If your car is using the early Injection system (flat topped manifold with eight bolts) rather than the later type (six bolts and taller sloping manifold) i'd be looking at changing the fuel filter and checking the electric pump. Also check the lines are plastic not metal. the SD1s with metal lines vapour locked very easily. If the engine is in a P6 it would be even worse as it is more confined.

However there is also a metal box next to or under the coil which contains related electronics. Take it apart and check the diode (big button pressed into the case with one central wire is NOT loose and stick some electrical tape to the cover in case it is loose when hot - they swing out and short to the case when turning in one direction or shortly after.
 

PepijnWK

Active Member
#6
If it starts and runs I'd be thinking your issue is probably fuel rather than spark. If your car is using the early Injection system (flat topped manifold with eight bolts) rather than the later type (six bolts and taller sloping manifold) i'd be looking at changing the fuel filter and checking the electric pump. Also check the lines are plastic not metal. the SD1s with metal lines vapour locked very easily. If the engine is in a P6 it would be even worse as it is more confined.

However there is also a metal box next to or under the coil which contains related electronics. Take it apart and check the diode (big button pressed into the case with one central wire is NOT loose and stick some electrical tape to the cover in case it is loose when hot - they swing out and short to the case when turning in one direction or shortly after.
Mike, that injection type was on there indeed the 8 bolt flat type engine. I took the injectionpart of and it is with carbs now. two SU hs6 are mounted now. This morning it fired right up though......

before:


now:
 

PepijnWK

Active Member
#10
Yep that is what I am assuming. I will order one and see what changes it brings me!

Thanks cobraboy for your feedback! it s very much appreciated!!
 
#11
Might be worth checking the coil input voltage (to ground). P6b's didn't run 12 v coils from the factory, they were all ballasted but the later ones had the ballast as a part of the harness so you can't see it. Ballasted systems have two wires on the coil input - one is twelve volt stater line from the starter solanoid, the other is the "running" wire from the ignition switch via the tacho - that is the (7-)9 volts ballasted wire.

The chap that built that injection system must have had a devil of a time getting the throttle to work. He has either turned the plenum around or it's off a rather rare NADA car. Australian SD1s which used that manifold have the intake on the opposite side. There are some photos of Triumph development cars with your arrangement. Maybe it was a left hand drive thing?
 
#12
one other electrical possibility is the pigtail wire in the distributor. It connects the sliding plate to the fixed plate and over time they break strand by strand giving erratic running. New braid for it can be bought from the local slot car (Toy) shop. to test loop a screwdriver under it and try to pull up. If it comes apart its no good!
 

PepijnWK

Active Member
#13
Might be worth checking the coil input voltage (to ground). P6b's didn't run 12 v coils from the factory, they were all ballasted but the later ones had the ballast as a part of the harness so you can't see it. Ballasted systems have two wires on the coil input - one is twelve volt stater line from the starter solanoid, the other is the "running" wire from the ignition switch via the tacho - that is the (7-)9 volts ballasted wire.

The chap that built that injection system must have had a devil of a time getting the throttle to work. He has either turned the plenum around or it's off a rather rare NADA car. Australian SD1s which used that manifold have the intake on the opposite side. There are some photos of Triumph development cars with your arrangement. Maybe it was a left hand drive thing?
Hi Mike,

it is certainly a lefthand drive thing! throttle was not that complicated. I made some pictures:



Mike do you know if the distributor can work together on the long run with a 12 volts coil without resistor?


ps the enigne runs pretty well now wthi the old Bosch coil. Tonight the new coil will arrive but I think the fact that I added 48 litres of petriol might have something to do with it...... So the petrol starvation issue was not a bad suggestion after all!!!!
another question Mike i hope you know is do you know on what engines these injections setups were placed? is it the low compression block? I am very curious since my engine has no numbers anymore.

I am willing to check the pigtail wire but I do not know what a pigtail wire is. Since English is not my native language could you explain what you mean?
 
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roverp480

Active Member
#14
"Pigtail" Its this type of wire earth lead from the base plate to the distributer body and the wire strands are braided rather than straight making it very flexible ,but can break over time. The picture is just an example. prod_large.jpg
 
#16
The Aus cars with that setup were 8.13 to 1 so low compression. They went into TR8s and SD1s in NADA territories and Australia/NZ my understanding is they all shared the same CR. there are two different places for the engine number, the second one is on the top of the ear at the rear of the engine, left hand side (throttle side in US) Comp ratio is stamped next to it

Carby P6s can also vapor lock and if the pump is electric it needs to flow lots of fuel due to the return line; so a blocked fuel filter will give erratic running. Note the Facet type factory electric pump has a strainer on the end that needs cleaning occasionally.
 
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