Rover v8 plugs 'n' carbs

[deano]

for the second time in the last few week the the spark plugs have developed a missfire as you accelerate. When you take the plugs out and turn the engine over there is a spark but intermitently it appears to jump from the ceramic nose rather than between the electrodes. Eitherway when new plugs are fitted the engine runs fine for around 100 miles then the missfire starts again and becomes progressivily worse. The plugs are black when I take them out so I assume its running to rich. Is it possible to run an engine so rich it buggers the plugs or does the problem lie elsewear.
Furthermore, one of the plugs is white does this suggest a valve problem when all the others are black and sooty.
Secondly the twin carbs are the later type with the mixture screw on the side. If I remember correctly you screw them out to weaken the mixture can anyone confirm this.#
thirdly Whilst I'm on the subject has anyone got a Rover V8 four barrel carb and manifold for sale at a sensible price.

cheers
deano

[dracken1]

ok, firstly check you have the correct grade plugs in.
i assume the engine is in a trike with plenty of airflow around them so called carbs, which i think are called hif models with the bi-metal strip which is capable of cutting off the fuel.
check oil level and beathers.
overly rich can cause spark scatter, is there signs of black smoke from the exhausts?. the white plug is unlikely to be a leaky valve as the plug would not be able to burn the mixture properly so it would be clean but wet.
its more likely an air leak in the manifold runner to that cylinder.

somewhere i do have a 425cfm 4 barrel holley with vacuum secondries on an edelbrock performer manifold.

unfortunatly the rover v8's reliability is also its downfall. as they are often neglected

has the engine been rebuilt? as incorrect timing, ignition and valve could show up in this way.

i used to race the old 3.5 for years in a celica and a mk3 cortina so know the engines pretty well.

[deano]

hi thanks for your reply The trike did the same again today after about three hours riding with new plugs. I'm now pretty sure the carbs are overfueling. also the engine has never had a decent tickover and there is evidence of black smoke when I blip the thottle. I'm pretty sure the carbs are worn so I would be really interested in the one you mentioned. I've sent you an email but I'm not sure if it sent ok my email is deandeanooo@aol.com
thanks again
deano

[dracken1]

yes i got your mail.
i will start looking tomorrow but in the back of my mind i seem to remember a guy with a v8 capri having it off me. but i did have an offenhauser also so maybe i still have it.

in my opinion hif carbs are utter crap, su's much better check the oil level in them. we used to use auto trans fluid in su's.
if one carb is lifting its needle to fast it would flood out the cylinders

[deano]

just had a look at the carbs this evening . The left hand one appears to be leaking we,ll not leaking as such but more of a dampness around the float bowl seal,. This might piont towards my problem. Meanwhile, while your looking for that manifold etc. If you come across something like a mallory dizzy and posh rocker covers etc I'll also be interested , Also a set of yellow plug leads, yeh I know that sounds strange but yellow would compliment my paint work.

cheers
deano

[ratwing]

I put a 2-barrel Weber (38DGAS IIRC) on the ex's Range Rover. A slight drop in performance but amazing fuel economy and cheaper than getting the clapped out Strombergs repaired. I gave the inlet manifold to Pegasus in Newington,Kent who planed off the pointy bit (technical term!) the carbs bolt to and welded on a flat plate to fit the Weber. Definately a mod worth considering if your carbs need replacing/repairing or whatever. I already had a new carb, similar are found on Ford Essex V6's, the re-jetting & manifold work came to about £100.

[deano]

As I live very near Kent The conversion by pegasus sounds like a cost effective and reliable idea. Have you got any contact details for them. and did they do the re jetting etc.
cheers
deano

[dracken1]

afraid i cannot find the carb/manifold set up. must have sold it to the capri owner.
the carb conversion to a 38mm 3.0 litre v6 one was quite popular.
i do have pics of it i'll post later . (i'm really sure i do have pics :) )

and as a trike should weigh less than a range rover there should be no probs performance wise.
if you decide to go the holley route, look for a 450cfm opposed to a 390.
under normal driving conditions a 390 is better but as a trike is a lot lighter than a car it will cope with a 450 just fine.
but mainly a s/h 450 is a lot cheaper than a 390.

or if you come across an edelbrock 500cfm even better, as it is basically a weber

[ratwing]

At work at the mo so haven't got their phone number, they're in Newington near Sittingbourne and do mainly LandRover/RangeRover/Disco. servicing/repairs. I gave them the carb & manifold and it came back ready to bolt onto the engine, all I had to do was to modify the throttle linkage (easy using bits of the RR linkage) & cables.

[deano]

Thanks for that. I should be able to get the number now. Hopefully the V8 will be a little more reliable and smoother running by next summer with a single carb at least it will be one less thingt to go wrong
. 3 times now I've had to limp home when the engine decides to become a V4 and a half Its all very embarassing and frustrating.

cheers
deano

[dracken1]

rpi are the rover v8 specialists
here is a link to thier edelbrock/weber page
http://www.rpiv8.com/carbs-1.htm

[ratwing]

Tried looking on the Land Rover Owner/Land Rover Monthly/Difflock websites for the dizzy & rocker covers? Lots of knowledgable guys there who know about the V8's too.

[deano]

thanks for your help I've checked out ebay and there is everything I need (except yellow plug leads)coming up over the weekend. a weber on a converted manifold, a holly carb and manifold and even some nice shiney but expensive rocker covers. I get my student loan though next week so I shall throw caution to the wind and get my bidding finger out I've got to get lucky at least once. meanwhile I've borrowed a colourtune setup so I'm gonna spend the day trying to make sense of the SU's that are currently fitted. There is a bike show thingy just outside maidstone at the weekend and I'm hoping the trike will be running well enough to make it.

wish me luck
deano

[Mad Dog]

I'll look out for you around Sunday lunchtime at Detling.

ps.
better wear a red carnation. :D

[dracken1]

THE HOLLEY 390 was the carb of choice untill the edelbrock/weber came on the scene.
not only is it a very good performer it beats the holley flat in the looks dept.
good thing on a trike when all can see it.
plus theres one on ebay atm

[deano]

acording to the colour tune when the mixture is about right the engine tickover is fine but has no power when you ride up the road. so in the end I set the carbs up rich again and the thing runs ok ish. I'm gonna have another fiddle with it tomorrow and hopefully it will be ok for sunday and detling. Meanwhile, I'll have to wait for the ebay auctions to run there course. If that fails rpi might be £560 (gulp) richer next week and have one less weber carb in stock.
A few of us are planning to go to delting on sun. (We've not been before is it any good) If we make it I'll be the bloke on the missfiring yellow V8 wandering round the trade stands looking for cheap BP6ES spark plugs. hope to see you there.
cheers
deano

[deano]

missfire reappeared on sat eve so did'nt make it to Detling on sunday. Anyway I got lucky on ebay and won a bid for a holly carb and manifold with the money I've 'saved' :confused: i've also ordered a Mallory dizzy from RPI. All the bits should be bolted on by Sat. so if that little lot dos'nt cure the problems there will be a cheap V8 project up for sale. :(

[dracken1]

what model dizzy? vacuum or electronic

[Blackjack]

Sounds like you need a new dizzy cap and rotor arm. DO NOT buy anything except a genuine one, as all the pattern ones are ****e.

[deano]

dizzy has vacuum advance and two sets of pionts. I've tried two different rotor arms and distributer caps and it made no difference. Basicly I've had enough of spending the last few weeks of reasonable weather in the garage rather than riding the thing. so splashed out a large portion of this years student loan to get the trike reliable (and hopefully a bit quicker :D ) I decided libaries lend books but not Rover V8 bits therefore I'll spend the money on stuff I can't borrow.