Lack of Power under Acceleration

[Deleted]

Hello

I have a P5B with AED.

After several months of happy motoring, the car broke down with a failed fuel pump. The pump has been replaced with an electric one. One bank of exhaust manifold gaskets was fitted (nearside) and all running well. Offside bank was then changed and the car will idle beautifully, will rev when stationary but as soon as you pull away, power disappears and it sounds like a multiple misfire. Points, condensor and coil have all been changed. Carbs checked and AED blocked off (as it was leaking petrol back in to the inlet manifold).

Is a duff servo likely to be the cause?

Thanks in advance for any help offered

Malcolm

[harvey]

Drive the car with the servo hose clamped to eliminate the servo as the problem. Just remember if you do that the brake pedal will be rock hard and it will be VERY difficult to stop. BE CAREFUL!
Have the manifold gaskets been fitted the correct way round, as if not they restrict the exhaust port. They aren't really meant to have gaskets anyway.

After that it's just a matter of systematically checking through all the normal suspects.

[Phil Nottingham]

If blocking off servo eliminates it ensure that its not the vac hoses or reservoir tank holed before swapping the servo. The brakes usually give trouble first

[Deleted]

I'm MalkyK's friend who works on the car. Don't think the gaskets are fitted upside down. We had to fit them as the manifolds blow like hell! Surprised they were never fitted as they fitted them later on. Not sure how to disimilar metals expanding and contracting at different rates are supposed to seal, but I have seen Ammerician engines like that before. Anyway, my suspicions on the servo is tha the friend who was helping me fit the gaskets knocked the cap off the atomsphere vent valve on the servo. I cliped it back on, but wondered about the sealing. Im going to discossnect the servo later and have a play again, but just if anyone had come across this. The fact that I have been throught the rest of the system with a fine tooth comb means I'm running out of ideas. I checked everything again last night, taking the seal(which looks very much like a tap washer) off and cleaning it. It looks as if the servo may have had a service kit fitted. The air filter is missing, but I never recall seeing it before (will try and source one) Of course, it could all be a complete co-incidence and there maybe another problem!

Also any advice on AED? I fitted a refurbished one with the car. Started out ok, then found it was dumping fuel in to the inlet manifold via hot air intake! The central diaphram? Are they worth the hassle?

[johnwp5bcoupe]

Re:-
"knocked the cap off the atomsphere vent valve on the servo. I cliped it back on, but wondered about the sealing"

Did the return spring get refitted

AED question has been kicked around a lot "do a search" I will keep mine as long as I can a lot of the guys have converted to manual when they have had problems.

[Phil Nottingham]

Most who have knocked off the servo air cap and lost the small lightweight spring that fits underneath.

As to gaskets P5B's never did have these and do not seem to give any trouble

The AED trouble is one of many it gets - they are not worth the hassle, evn Rover gave up in the end and offered a conversion kit. They can be made to work though

[Deleted]

Change the fuel filter.

[Deleted]

Fuel filter has been changed so we're going to concentrate on servo and scour the garage floor to see if there is an errant spring.

[theroveringmember]

slant4 said:

Also any advice on AED? I fitted a refurbished one with the car. Started out ok, then found it was dumping fuel in to the inlet manifold via hot air intake! The central diaphram? Are they worth the hassle?

No! ;D

[Deleted]

Everything appears intact and working in the servo. I havent taken it down the road yet but not hopeful. I assume we are the not the only ones to fit manifold gaskets to the exhaust? They were the genuine part, just wondered if ther eis an issue there. Surely Rover didn't alter them that much? The SD1 range and land rover had them.

Inspiration pelase!

[Deleted]

Still on the fuel supply, how about the tank filter or a duff reserve tap. They need a lot of fuel on acceleration.

[Deleted]

tell me more, tank filter?

[Deleted]

just checked tap and it free
had a long chat with burdens re aed and other poss issues very helpful but they have no more aed spares!

[Deleted]

slant4 said:

tell me more, tank filter?

The top of the tank has a panel that comes out and contains the pickup and reserve pipe. Removing will reveal the filter.

[theroveringmember]

You can try these people too:- www.gowerlee.dircon.co.uk/
Not sure if they can help with the AED but you can try & if you decide to do the right thing & throw it away they have manual conversion kits.

[Deleted]

Dealt with Gower and lee for years. Real good company. Will pull out the filter and have a look.

[johnwp5bcoupe]

Also:-

www.burlen.co.uk/partSearchList.aspx?partSpec=aed

HMMMMMMMMMM

if you decide to do the right thing & throw it away

After driving a car at the weekend with manual choke I am even more of an AED fan

[Deleted]

My AED did work for about four years after I bought the car but played up when driving past Harrods to see the flowers at Kensington Palace 10 years ago.
I obtained and fitted a manual conversion on top of the AED and have never looked back.
The car starts well and runs better, when the choke control is off, the choke stays off. Fuel consumption must be better since we only require sufficient choke to start the car and can quickly shut the choke off (depending upon the ambient weather).
No regrets about manual conversion at all.

[johnwp5bcoupe]

I know the conversion freddy that works fine if I do any conversion I will use the electrically operated shut off valve

[DaveCole]

Hello
The symtoms you descibe sounds like ignition problem rather than fuel.

Could be the points gap. If the gap at idle is only just within 24-26 degrees dwell angle idle will be OK, however when you accelerate the vacuum advance moves the points to match best ignition timing for revs, if set incorrectly the gap becomes to big for a strong spark and you get loss of power and misfiring as you describe. Also check vacuum advance is working OK

regards
David

[johnwp5bcoupe]

Good advice David when I did Glenn's Dizzy at the weekend he had about 15 thou movement on the shaft what was that doing to the dwell angle

[harvey]

I think you'll find that the dwell should be 26-28 degrees, not 24-26.

I don't understand what you're saying about the dwell being altered by the vacuum advance either. As you accelerate it's the mechanical advance that alters the timing, and this has no effect on the dwell. If what you say is correct, the faster the engine revs, the wider the points gap becomes, which is not correct.
You seem to be muddling up dwell and timing.

[johnwp5bcoupe]

Harvey knows his onions

[harvey]

johnwp5bcoupe said:

Harvey knows his onions

Shame I don't know as much about Rovers!

[Deleted]

checked points all ok, dwel in spec, vac system checked early on all fine. Just in the process of looking at the tank pick up filter?!