New C3 owner, already bad news!!
Discussion
Hello all,
I was hoping to arrive on here today and tell you all how chuffed I was that I'd got myself a C3 that I'd been wanting for ages and how brilliant it was.
Unfortunately not 12 hours after buying it I'm already having issues. On the drive back from buying it yesterday all was fine until the end of the journey. But I'll give you a quick history first:
- '77 C3 with a new engine this may (brand new crate engine), EB Supercharger, new radiator, replaced longer ratio diff etc etc.
- Went for test drive on Monday. All was well.
- Bought on tuesday, started from cold first time, and after letting it warm up on the sellers drive, drove back to my house 90 miles away, through bad traffic and also open motorway. No issues, car ran fine.
- End of motorway, coming into my town at home, I came off the throttle and the excess fuel in the system backfired through the supercharger (the seller warned me to always keep revs up in order to avoid this, dropping into lower gear for roundabouts etc, which I did do). Carried on ok, but then a mile from home turned up a hill and again had a backfire and stalled. Restarted and just managed to get home, with one more stall just before I got back.
- Once back and safe, tried restarting, which it does fine, but as soon as I come off the throttle and its returns to idle revs it cuts out. If it was cold this would have been understandable, but this was at the end of a long journey and the engine was more than warm.
- Tried again this morning but the same problem is happening, often with a loud pop out of the SC when revs are dropped and excess fuel explodes.
As you can probably imagine I'm fairly upset about this. I want to give the seller the benefit of the doubt as he seemed a geniune guy and had obviously spent a great deal getting the car to where it is with new engine etc.
Anyone got any idea what my be causing the issue? I can't drive it now as it won't idle at all, so I can't even get it into gear before it cuts out. I'm guessing its a fuelling or carb problem of some sort, but I'm not overly mechanically minded.
Any help would be massively appriciated!
Voguely.
I was hoping to arrive on here today and tell you all how chuffed I was that I'd got myself a C3 that I'd been wanting for ages and how brilliant it was.
Unfortunately not 12 hours after buying it I'm already having issues. On the drive back from buying it yesterday all was fine until the end of the journey. But I'll give you a quick history first:
- '77 C3 with a new engine this may (brand new crate engine), EB Supercharger, new radiator, replaced longer ratio diff etc etc.
- Went for test drive on Monday. All was well.
- Bought on tuesday, started from cold first time, and after letting it warm up on the sellers drive, drove back to my house 90 miles away, through bad traffic and also open motorway. No issues, car ran fine.
- End of motorway, coming into my town at home, I came off the throttle and the excess fuel in the system backfired through the supercharger (the seller warned me to always keep revs up in order to avoid this, dropping into lower gear for roundabouts etc, which I did do). Carried on ok, but then a mile from home turned up a hill and again had a backfire and stalled. Restarted and just managed to get home, with one more stall just before I got back.
- Once back and safe, tried restarting, which it does fine, but as soon as I come off the throttle and its returns to idle revs it cuts out. If it was cold this would have been understandable, but this was at the end of a long journey and the engine was more than warm.
- Tried again this morning but the same problem is happening, often with a loud pop out of the SC when revs are dropped and excess fuel explodes.
As you can probably imagine I'm fairly upset about this. I want to give the seller the benefit of the doubt as he seemed a geniune guy and had obviously spent a great deal getting the car to where it is with new engine etc.
Anyone got any idea what my be causing the issue? I can't drive it now as it won't idle at all, so I can't even get it into gear before it cuts out. I'm guessing its a fuelling or carb problem of some sort, but I'm not overly mechanically minded.
Any help would be massively appriciated!
Voguely.
Personally, if it was me I'd drive it straight back. One of the Surrey club members had a SC fitted to his C5 and it gave him nothing but serious trouble for the 4 or 5 years he had it fitted.
Only in the last few months he put the whole car back to standard and whilst missing the extra performance, it at least now gets him to where he is going each time. It didn't before.
Just because it's a private sale doesn't mean you don't have recourse.
Only in the last few months he put the whole car back to standard and whilst missing the extra performance, it at least now gets him to where he is going each time. It didn't before.
Just because it's a private sale doesn't mean you don't have recourse.
Driving it straight back would be great - if I was able to drive it anywhere!
As for getting rid of the SC - possibly a better idea, which I'd already considered. Hopefully I'd be able to sell the SC 2nd hand for enough to cover any other parts to put it back to normal too, although it would need a new bonnet without a hole in the middle too!
I'll have a look for vaccum pipes, cheers.
As for getting rid of the SC - possibly a better idea, which I'd already considered. Hopefully I'd be able to sell the SC 2nd hand for enough to cover any other parts to put it back to normal too, although it would need a new bonnet without a hole in the middle too!
I'll have a look for vaccum pipes, cheers.
Firstly what blower is being used - is it blow through? is it a Gimmy style draw through blower (mounted on top of inlet manifold with carb on top) - is it carbed? - what carb is it? - if a Holley (or derivative) backfires will rupture power valve in carb and cock-up running. You don't want a Vette specialist - a specialist in Yanky engines with experience in blowers would be more useful. What past of Essex are you? - its Essex Vette club meet tonight at Red Lion Margaretting - come talk to us - Rdgs, Ross
roscobbc said:
Firstly what blower is being used - is it blow through? is it a Gimmy style draw through blower (mounted on top of inlet manifold with carb on top) - is it carbed? - what carb is it? - if a Holley (or derivative) backfires will rupture power valve in carb and cock-up running. You don't want a Vette specialist - a specialist in Yanky engines with experience in blowers would be more useful. What past of Essex are you? - its Essex Vette club meet tonight at Red Lion Margaretting - come talk to us - Rdgs, Ross
Ross,Thanks for the kind offer of joining you - I may well do so in future when I've got a working car! My main car is down in Hampshire at the moment, so I can't even come in that! I'm in Colchester, you?
It is indeed a holley carb, mounted on top of the SC which is on top of the engine. (intake is out of the bonnet). SC is an Edelbrock.
When I spoke to the guy at Corvette Kingdom up in Norfolk earlier he said himself that he thought it could have been the valve damaged by the SC backfire, so you may well be right.
Do you know anyone around this area who is a yank engine specialist by chance? Who do you use to look after yours, or are you mechanically minded enough to maintain it yourself?
To previous poster - yes, I called the seller, he knew that it backfired if revs were dropped too quickly then back on the throttle again - for example coming upto a roundabout in too high a gear, but said he hadn't had any issues like I'm having. It is quite difficult to keep the revs up though in this, being an automatic manual, even taking it down into first on approach to junctions it still seemed to be collecting too much unburn fuel and causing these backfires. Maybe the fuelling needs to be adjusted down.
I'm really hoping I can get this fixed and it isn't anything too horrendous, its such a beautiful car otherwise!
I can suggest Terry or Andy of T & A motors who have respectively have workshops in Billericay and Basildon. They have been involved with Vettes and yank powered stuff for 30 plus years and may be able to help you - although as I said earlier this is not a Vette specific problem - Andy is on 01268 590891. The problem with these type of blowers is exactly the one you are experiencing i.e. excess fuel puddling in the blower casing if the carb isn't set-up correctly. It sounds as though you may have an issue with the ignition timing too causing the backfires.
Edited by roscobbc on Wednesday 19th September 23:02
roscobbc said:
I can suggest Terry or Andy of T & A motors who have respectively have workshops in Billericay and Basildon. They have been involved with Vettes and yank powered stuff for 30 plus years and may be able to help you - although as I said earlier this is not a Vette specific problem - Andy is on 01268 590891. The problem with these type of blowers is exactly the one you are experiencing i.e. excess fuel puddling in the blower casing if the carb isn't set-up correctly. It sounds as though you may have an issue with the ignition timing too causing the backfires.
Thanks again, although just called Andy and he said that he's retired now which is a shame (for me, good for him obviously, ha!)Edited by roscobbc on Wednesday 19th September 23:02
Having had a couple of supercharged cars (albeit injected), I wouldn't want to take it off!
The fact that it worked fine from cold and for the entire drive home would indicate that it's not a massive problem, but, as stated already, more than likely a minor problem caused by a blow-back through the carb. Not much help, I know. I'm sure once sorted, it'll be a fantastic motor. Looks great; I've got a soft spot for the C3 (and the C1, C2 and C5-C6)
The fact that it worked fine from cold and for the entire drive home would indicate that it's not a massive problem, but, as stated already, more than likely a minor problem caused by a blow-back through the carb. Not much help, I know. I'm sure once sorted, it'll be a fantastic motor. Looks great; I've got a soft spot for the C3 (and the C1, C2 and C5-C6)
Tom Newman at West Mersea should be able to help you http://www.misterwhat.co.uk/company/2633177-tom-ne...
Thanks for all the replies guys, much appriciated. Seems there are a few American motor types hiding in various places not too far away from me! Hopefully if it is a blown valve in the carb then it can be fixed without costing the earth and then with a bit of timing/fuelling tuning it won't do it again and I'll be on the road once more!
p.s. James, that's a lovely C3 you've got in your profile! Are you around this area too?
p.s. James, that's a lovely C3 you've got in your profile! Are you around this area too?
Edited by Voguely on Thursday 20th September 20:07
Voguely said:
Thanks for all the replies guys, much appriciated. Seems there are a few American motor types hiding in various places not too far away from me! Hopefully if it is a blown valve in the carb then it can be fixed without costing the earth and then with a bit of timing/fuelling tuning it won't do it again and I'll be on the road once more!
p.s. James, that's a lovely C3 you've got in your profile! Are you around this area too?
Sorry, buried in Dubai for the last 2.5 years - got a 1970 Stingray here running a small block!p.s. James, that's a lovely C3 you've got in your profile! Are you around this area too?
Edited by Voguely on Thursday 20th September 20:07
Vette_1978 said:
You won't find anywhere better than Corvette Kingdom. My C3 has been there for engine rebuild, new gearbox and got transported there after LMC08 when u-joints sheared. I'm down there on Oct 6th for a bit of Scott's TLC...the car is, not me!!
Seconded. Scott is a font of knowledge on all things Corvette and will give you an honest opinion based on years of experience.G
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