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teething problems- carb I think....
phil4521 - 26/6/11 at 08:51 PM

Took the Viento Rover V8 out for a blat today- fab weather and it was magic. Done 200 miles now so things are starting to bed in although the suspension creaks like hell to start...... Over 30 degrees today and was happy I had no over heating problems. However- when she gets hot, there is noticeable delay when I put my foot on the accelerator- the engines seems to die then picks straight up again. When put my foot down when she is stationary, you can see smoke coming out of the exhaust leading as the engine picks up- leading me to think it may be carb adjustment/ jetting? its Weber 500 out of the box. I have mixture set by a tuning guy and tick over is fine. Any thoughts?


RichardK - 26/6/11 at 09:00 PM

Think a rolling road session would sort that, reckon it just needs rejetting.

Cheers

Rich


wilkingj - 27/6/11 at 04:27 PM

The suspension creaks as the crush tubes are a bit on the short side.
You need to either:-
A. Remove some material off the outside of the polybush.
or
B. Buy longer crush tubes. (Expensive option)

This is well doccumented on LCB, and I have done mine, and got it down to just a couple of creaky bushes where I didnt take quite enough off the bush.

If you have access to a lathe, take the suspension arms off the car, then insert the crush tube in the bush and put it in the lathe.
Skim off a very small amount (mine were 25 thou each side... ROUGHLY)
Do both sides of the bush, reassemble that bush in the Arm, then Grip the bush and arm in a vice, and try to move the arm up and down, ie suspension movement type of thing. Skim and adjust until you get free up/down movement with NO lateral play.
Take it slowly, as if you take too much off the bush will be scrap.
Do this for all the bushes and then re-assemble on the car. Do a test drive, and you should find the car drives a whole lot easier. and the suspension then works (and works quietly).

DO NOT, slacked the M12 suspension bolts to make the arms move more easily as this with wear the mounting bracket holes OVAL, and you will need to replace the brackets which IS a bigger job. Thes bolts need to be done up tight.

A smear of silicone rubber grease also helps on the bushes. £3 a tube from Maplin - NOT the spray on juice, the Tube not shown on their website but is available in the shop.

Its not a difficult job to do, just a bit of time and patience. The result is well worth the time spent.

Check posts by Rusty Nuts on this subject.


See Also :-

http://www.locostbuilders.co.uk/viewthread.php?tid=123345

http://www.locostbuilders.co.uk/viewthread.php?tid=150685

http://www.locostbuilders.co.uk/viewthread.php?tid=139159


Hope that helps.



Paul (Notts) - 27/6/11 at 07:29 PM

My webber 500 ( new) needed the float heights adjusted to help it stop bogging down on hard acceleration.(simple job - if you need the right size drill bit to set height I can send you a spare)

+ if black smoke on acceleration then the acceleration pump is set too high.

Paul


simonk - 1/7/11 at 12:00 PM

Hi Phil - when are you going to bring it round then ??

Mine does exactly the same thing, tiny cough when you plant the throttle before taking off like a scalded cat, starts to smoke and cough a bit on repeated throttle blips at slow speed ( I know.. I know.. but what's the point of a V8 if you don't ?) Hasn't been enough to bother me really, but thinking about it I agree with Paul that perhaps the accelerator pump needs calibrating - however on reading the Edelbrock tech stuff they suggest increasing the accelerator pump delivery if the engine bogs or coughs as the secondaries open, as the engine gets more air immediately the chokes open but the fuelling can't keep up......... I'll give it a try this weekend and let you know.

http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

The other thing they mention is the 7 degree carb levelling plate. In the Viento the engine sits flat and as a result the Edelbrock manifold will incline the carb towards the front of the car and you won't get your floats to work consistently. I got my levelling plate from DJE but I imagine any of the V8 guys will be able to supply.

Good luck Phil !
Cheers
Simon


Steve Lovelock - 2/7/11 at 11:36 AM

The bast way to solve the squeaking suspension is to change the bushes and tubes for a proper set. The Leugo supplied items are rubbish. It's not cheap but it is the proper route to take. Superflex supplied mine and they have been perfect every since.


Angel Acevedo - 11/7/11 at 05:13 PM

Your problem with the carb sounds like a Cam Actuated Trottle pump, this pump squirts a jet of fuel when you floor the throttle to account vor loss of air velocity during sudden acceleration.
The pump must have provisions for adjustments.
Someone will post with correct procedure for adjustment but basically you reduce until there´s no hesitation...
HTH
AA