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Discussion Starter · #1 ·
Hi All,

I just joined the forum and its my first post. I acquired a RR shadow a few months back with a destroyed engine. The thing blew up and put a hole through one of the pistons. the previous owner disassembled it down to the block and left it all in bins for quite a few years. In any case, i bought it and began the engine swap and parts puzzle from the 2 giant bins i had in the trunk. the previous engine was a leaky monster that gunked up every piece of the undercarriage. bad for cleaning but good for rust prevention. I dropped the front chassis and swapped the new core in and pieced together the rest of the motor. this was last Tuesday. By Friday the new engine was rigged up running on the front suspension with no smoke (just headers as well) By Saturday we removed all the hydraulic brake parts from the engine bay in favor of a hydroboost conversion and engine was reinstalled. Sunday we tightened all the underbolts and dropped the car down for top wiring. Thats the story so far and it is moving along at a fast pace. I got slowed down as i was working off memory from treading through the manual the week before. Now i printed some diagrams and will finish hooking up my smog stuff and vacuum lines but ran into one problem. The engine wont crank from the key. wiring was not really touched although i had to remake the portion that went to the starter as it was brittle. wires were tested but i'm not getting any power down there. in the wiring is there a relay or some sort of switching system that needs to be engaged before the starter can turn over? I didn't have time to dissect the wiring schematics yet and didn't want to spend too much time looking into it as the car was intact aside from engine being torn apart. Hope you guys can shed some insight on this problem, and look forward to giving you all some light on the new braking system in case anyone would be interested in converting their cars.

Thank you all for the help

Andrei
 

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starter is wired through oil pressure light switch so you can only start engine if there is oil pressure. pull off wire from oil pressure switch (should be be single wire on sender) and try that
 

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Discussion Starter · #3 ·
that would be a problem, but i wonder if it is the other way around, as i did not have the oil sending unit connected right now. so it is not seeing a ground when ignition is on but engine is off. I will give that a try in a couple of hours. hope it works.

Thanks for the quick reply.

Andrei
 

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There's a starter solenoid which powers the starter; there's a starter relay which powers the solenoid. The relay has two cut-outs: one to make sure the gear selector lever is in Park or Neutral, and one to make sure the tranny itself is in Park or Neutral.

I think the oil pressure switch rollmech mentions only controls the fuel pump relay: so you might not get it to fire, but it should turn over.

-- Jeff.
 

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Or maybe not....

On the Shadow II, the fuel pump relay grounds through the oil pressure sender -- so you'd need to connect the lead to ground rather than leave it disconnected.

But... it looks like your car may not have the oil pressure sender wired into the fuel pump relay at all (according to the not-always-accurate theoretical wiring diagrams).

Anyway, make sure it's in park first....

-- Jeff.
 

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Discussion Starter · #6 ·
that does make some sense. as when i was connecting the linkage i noticed i had to pull it out of park to match it up to the acctuator, but my lever was on the park position. and i did not hear the trans shift back into park. Is there a trick to resetting the transmission gear position to match up to the column shifter?
 

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The column-mounted stalk connects different contacts for each gear. There's a slip-ring on the gear actuator worm wheel which has gaps which kills the power to the actuator motor when the right gear is reached.

There's also a cam which engages the park, reverse and height-control microswitches. The workshop manual doesn't give any procedure for adjusting them, so I expect the slip-ring and cam must have some sort of positive location to keep them aligned.

So while it may be an issue for cranking the motor, the starter motor should attempt to engage even if the gearbox and selector aren't aligned (only the microswitch in the actuator and the selector need to be aligned).

I'm not sure that helps you, though....

-- Jeff.
 

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Discussion Starter · #8 ·
well it all worked! the shift rod wasn't properly adjusted (tranny was in N when the box was at P position) and the neutral safety switch is bad, which was probably the reason why it was disconnected when i removed the subframe. Car started right away with the fuel in the bowls, but died shortly after due to the lack of fuel from the SU pump. weird thing is that i heard it make some popping noises then nothing at all. i think i will swap it out for a reliable holley unit wired without the oil pressure switch.


thanks for the help.

Andrei
 

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Well done, Andrei!

BTW, which neutral cut-out switch is bad? The column mounted one or the one in the gearbox actuator?

(I did notice a setting procedure in the workshop manual for the proper clearance between the microswitch and the cam in the actuator - so if that's the one giving trouble it might just be out of adjustment.)

Cheers,
Jeff.
 

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Discussion Starter · #10 ·
it is the switch in the transmission, that has the spade tabs in a L or T formation. odd thing is that there is only one wire connecting to that switch which leads me to believe it is a ground based switch, and that it is jammed.

I have to say this has been the smoothest engine swap to date. although it is the first one i have had the use of a proper lift to raise the car, and a 7000ft shop with plenty of lighting.
 

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Andrei,

The netrual start switch is the bottom of the stack of two (the top is the height control switch which changes the rear height control from fast mode to slow mode when in drive).

The neutral start switch should have 2 wires on it: white/red and white/black.

The switch all by itself is for the back-up lights, and should have 3 wires: green/yellow, white/brown and green/blue. (I think the green/yellow just goes to the height control switch.)

Of course the wiring diagrams disagree with each other in places, so take all that with a grain of salt....

Hey, just noticed you're in San Jose. I lived in Willow Glen for about 10 years and then up by Alum Rock Park for another 8. Where-abouts are you?
 

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Discussion Starter · #12 ·
i'm in Willow Glen , by Pine. What a small world. Where are you located now?

I used to work in my drive, but now i'd rather drive to Walnut creek and work in the shop where theres no crawling and bad weather involved.


also on my trans i only have one switch on the left hand side. but a big harness at the controller box.
 

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We move to Ireland in 2006. (Had been going back and forth for about 10 years restoring an old house. Finally got it more-or-less complete and thought it would be a shame not to live in it.)

Cheers,
Jeff.
 

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Andrei,

If you have not already done so, get yourself over to the RROC-Australia Post-War Technical Library, go to the SY (Shadow & Derivatives Section) and start downloading. It's very handy to have the Workshop Manual and to be able to browse the spare parts manual online.

Also, be sure to visit the
RROC-AustraliaTee-One Topics Archive, where virtually any repair you can think of has probably been discussed. The index through issue 63 is invaluable for locating articles of interest.
 
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