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slow 1981 2L Aircooled
Posted: 11 Mar 2008, 11:19
by jamesdevon
Hello people,
My bus has been off the road for a while, It's just had a new vege 2L Aircooled in it and I'm getting it ready for a road trip. Everything is fine except it's slow, 60mph tops and rubbish on hills. I'm thinking the carbs may be clogged, is there anyway to check this or anything else I can check? It runs totally smooth other than this power issue. There is plenty of fuel being pumped to the engine bay and the vacuum on the dizzy is working fine.
Thanks
James.
Posted: 11 Mar 2008, 12:33
by Joda
Could be your carbs are not opening up enough. Check for any slack in accelerator cable and adjust if required.
If the carbs need cleaning - use some carb cleaner easily available from local motor shop
Posted: 11 Mar 2008, 14:51
by fergus77
If it's a 2.0L CU engine then don't expect much more than 60mph on the open road.
My old Westy had the 2.0L CU and it was terrible, thirsty, slow. Going up hills was a whole reving match just to get maybe 20 - 25mph up a stepish one, if even that

Posted: 11 Mar 2008, 16:20
by Mocki
cobblers!
the CU will easily do 80, and maintain it as long as there are no hills.....
id say you either aint getting enough throttle movement, or the carbs need setting up...... or its not that good an engine.......
Posted: 11 Mar 2008, 16:24
by Joda
Mines a CU and will easily do 80 (even if it does take a while to get there, but then why rush)
Posted: 11 Mar 2008, 16:47
by stretch
new engines are still tight for a couple of thousand miles dont expect too much until you have some miles under your belt
Posted: 11 Mar 2008, 18:02
by Rozzo
mines a cu and i went up windy hill on the m62 at 65mph in top when i got it. it easily did 80 too but it dont now cos i've backed the throttle off to preserve things and it now does 65 flat out

Posted: 11 Mar 2008, 20:21
by jason k
Rozzo wrote:mines a cu and i went up windy hill on the m62 at 65mph in top when i got it. it easily did 80 too but it dont now cos i've backed the throttle off to preserve things and it now does 65 flat out

the thing is the more you rev em the cooler they are, dont labour up hills in top, drop it a cog and rev the "bar-steward"!!!
cus are a great motor if set up properly.
get it to a rolling road and let them time and jet it and you will see a different van.
i use
www.raceshack.co.uk
Posted: 11 Mar 2008, 23:44
by The_blue
Mocki wrote:cobblers!
the CU will easily do 80, and maintain it as long as there are no hills.....
id say you either aint getting enough throttle movement, or the carbs need setting up...... or its not that good an engine.......
I agree, mine will sit at 80 on motorways if needed, even hit 95 down hill into Newcastle last year.
far scarier than anything at Alton towers when the side wind hit!
Posted: 12 Mar 2008, 12:59
by richnewton
jason k wrote:Rozzo wrote:mines a cu and i went up windy hill on the m62 at 65mph in top when i got it. it easily did 80 too but it dont now cos i've backed the throttle off to preserve things and it now does 65 flat out

the thing is the more you rev em the cooler they are, dont labour up hills in top, drop it a cog and rev the "bar-steward"!!!
cus are a great motor if set up properly.
get it to a rolling road and let them time and jet it and you will see a different van.
i use
www.raceshack.co.uk
just out of interest, how much does a session cost?
Posted: 12 Mar 2008, 13:36
by Laurie
If your carbs are opening fully, your carbs are balanced, your timing is correct, your distributor vacuum is working as well as the centrifugal advance. If your tappets are adjusted properly, have the flaps fitted, even if they're open, you've thrown the idle stabilizer away, have a decent engine seal, have a clean fuel filter, have a fuel pump working properly, have all your wheels running free, have the 2 litre box, isn't a massive high top or a Karmann Gipsy and all the etceteras. Your van should be running right. No need to waste your money at posh places.
If your local specialist can't diagnose it, he should get a job at Morrisons, pushing trolleys.
I'd start with tappets because Vege often weld heads and the valves settle in quite radically at first. Then I'd look at carb balance. Then timing and dissy condition. The filter nearest the tank. The hoses. Some daft buggers are saying that the hose should be 5mm. It is 5.5 0r 6 depending on supplier. Sometimes there is a piece of 8mm to the pump too. 5mm is restrictive. Throttle opening is important. On the left hand carb is an electrid cut off, about 1" round with a single connection. If that is loose, or askew the carb may well be knackered.
Do remember that the engine is only 68BHP and my experience of them is slightly more conservative than some of the posts on here. Give me a good 1700 or 1800 any day.
Posted: 12 Mar 2008, 22:37
by jason k
richnewton wrote:jason k wrote:Rozzo wrote:mines a cu and i went up windy hill on the m62 at 65mph in top when i got it. it easily did 80 too but it dont now cos i've backed the throttle off to preserve things and it now does 65 flat out

the thing is the more you rev em the cooler they are, dont labour up hills in top, drop it a cog and rev the "bar-steward"!!!
cus are a great motor if set up properly.
get it to a rolling road and let them time and jet it and you will see a different van.
i use
www.raceshack.co.uk
just out of interest, how much does a session cost?
my first ime where i had the solexs jetted as they tend to run lean at the top end cost me £180. that included 4 rolling road runs and the jets being drilled. also gave me seven more horses at the wheels!!!
Posted: 12 Mar 2008, 23:31
by Laurie
7 more than what? When the engine came in, or than standard. ie. 75 BHP? 10% up on the original?
I'm not arguing, just trying to get people to check that the thing is set up right in the first place. That isn't just down to carbs, it's down to all the things I mention.
We used to have staggering results when we used Aldon Automotive, 20 years ago but time taken making sure all the other things were right kept the cost down.
Posted: 12 Mar 2008, 23:33
by jamesdevon
Thanks for the replies, I will keep you posted. I had a CU in the past and it's always chugged along quite happily at 75 no worries, with a high top roof. The fuel lines (5mm) and filter are new and the pump is good.
When you say if the carbs are fully open.... once the engine is warmed up after a 12 mile run and you remove the airfilter and look into the carbs, should the main disc be fully up on each carb so you can see in clearly. because the one on the left carb was on a 45 degree angle while the disc on the right carb was straight up?
The other thing i was thinking is if the exhaust has been stood around on an engine for ages could it get blocked up and cause this?
Posted: 12 Mar 2008, 23:40
by Laurie
You found the first problem. The choke should be straight up after 12 miles.
You may find that if you give the engine a hearty rev, the choke which is not fully open chatters and may even close.
Loosen the 3 screws holding the choke unit on and turn the choke until it is upwards.