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Carburetors - Loose Screws

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healeygal

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Yesterday, I went for the first long club ride in my Healey after getting her all back together and on the road. It was a trip to see the poppies in San Diego county with the Corvair club, as I had missed the one with the Healey club. A little past the town of Julian we stopped for gas, and whose car wouldn't start again after the brief rest stop - argggh!!! It kept dying out - each time I would start it, the best it would idle at was about 400 rpm and start to fade out, but if I would step on the gas and start driving, even though it was gasping and sputtering, once down the road a bit, it would run fine! This happened two more times during the day. Thoughts of vapor lock and altitude were mentioned, but the weather was pretty cool and Julian is only 4000 ft. I had changed my fuel filter last month because the car was acting very similar to yesterday's problem, and at that time, the filter did have some very fine sand-like grit, so one possibility was more of the same. But I've put on several hundred miles since then with no problem 'til now.

Today, I removed the fuel filter and clear fuel and no grit or any debris at all came out. Because my car has a problem with nuts, bolts and screws vibrating loose, I started tightening the screws described as "chamber to body" in the Moss catalog. One of the three was loose on each carb. (These were not the "stop adjusting" screws described in the catalog.) When I tightened them down, the engine idle sounded a little stronger, and it's idling at 700 now. Is it pretty likely these loose screws were the cause of the problem? I don't want to drive 150 miles back out to Julian to find out!

Sharon
BN1 on the road again
 

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[ QUOTE ]
When I tightened them down, the engine idle sounded a little stronger, and it's idling at 700 now. Is it pretty likely these loose screws were the cause of the problem?
Sharon
BN1 on the road again

[/ QUOTE ]
Hi Sharon,
It's pretty likely that this was the problem. A vacuum leak at this location would definitely alter the fuel mixture as well as interfering with the operation of the carb pistons. It is likely that the problem was becoming progressively worse as you drove. You should be able to tell in a short time if it is fixed. It might not hurt to have someone show you how to check carb sync & fuel mixture.
Regards,
D
 
I doubt that the altitude was a factor -- my SUs perform well from 1000' to 10000', some loss of power I suppose but hard to detect it as it is either extreme uphill or downhill.

Hopefully those loose screws were the answer but I would not have thought just 1 of 3 loose on each carb that would create a vacuum leak. Not doubting Dave... just suggesting that a test drive is in order.
 
HI Sharon, That certainly could cause the problem.However, rather than just a single loose screw I think you may have the bell skewed a bit.I have run into this problem before and the cure seems to be using a different sequence for tightening the screws-try more than one. This cured the problem on a couple of cars I have had this problem with.--FWIW---Keoke
 
I didn't check the photo first time around -- looks like SR78 by the Tamarisk Grove campground in Anza-Borrego State Park. That is indeed a fine drive.
 
I know the guy who owns the Julian Hotel (1897s)and restored it. He use to have an MGA. Great open curvy roads. Mostly free of snow. I'm jealous. Shorts! We are still getting snow and 20 degree mornings. (Okay though. I'm still redoing the upholstery and exhaust. Two more weeks.)
Sharon, the new paint looks very nice.
 
Hi all,
Thanks for the tips and info.

Dave,
A friend is coming Wednesday to take a look and double check - maybe he can explain carb sync and fuel mixture, and maybe, just maybe I'll be able to understand what he's talking about!

Keoke,
Lined up and re-tightened the bell and went for a 20-mile ride. Also added a bit of carb oil, and now everything seems fine.

Patton,
It was fun being sandwiched in between the two Corvairs. The white one has roller rockers and the red one is a turbo. It also has knock off wire wheels - must have been a rare option!

George,
Yup, that's the Grove right off of Highway 78 - real pretty countryside. Stopped for a picnic lunch and went for a 1-mile hike to see the flora and fauna up close.

Tahoe,
Re the paint - thanks!
Yes, we've been having some great weather down here - blue skies with white fluffy clouds scattered about, but we had to go 100+ miles from Orange County to get to those scenic roads, many of which were freeway miles (loud groan). You're lucky in that you get to live in those beautiful surroundings at Tahoe year round!

Sharon and her BN1 getting in shape for Klamath /ubbthreads/images/graemlins/driving.gif
 
Hi Sharon,

She looks great out on the road! /ubbthreads/images/graemlins/thumbsup.gif

Did you guys stop at Dudley's Bakery? I can never make it through that neighborhood without loading up a bunch of bread to go. (obtw – you can get from OC to Julian without much, if any, freeway mileage. The back roads through Temecula are really, really cool. It just takes a little planning and a lot of extra time.)

Speaking of motoring about San Diego County, are you planning on bringing her to Rolling British Car Day?


See Ya,
PC.
 
[ QUOTE ]
Yesterday, I went for the first long club ride in my Healey after getting her all back together and on the road. It was a trip to see the poppies in San Diego county with the Corvair club, as I had missed the one with the Healey club. A little past the town of Julian we stopped for gas

[/ QUOTE ]

Yikes and double yikes...I was there on Friday!!!! /ubbthreads/images/graemlins/thumbsup.gif
 
Sharon we would call them dash pot holding down screws over here, and if even one screw was loose it would definitely effect the performance of the piston inside. Have you got any split anti vibration washers installed with your screws and nuts, they do help ----- a bit, having said that, one of my rear shockers came loose just before Christmas, such a terrible squeek, and that did have split washers, so even they are not fool proof.

Bob/ubbthreads/images/graemlins/england.gif /ubbthreads/images/graemlins/cheers.gif
 
Bob,
I noticed the washers in the Moss catalog. Don't think my carbs have them - will have to double check and get some. But your're right - I've noticed that even with washers, things vibrate loose on my car!

PC,
Yes, we stopped at Dudley's - got a bunch of breakfast pastries which are already gone. Will have to check into the "backroads through Temecula" suggestion - sounds cool!

I'm planning on going on the Rolling British Car Day ride. Since it starts at 10:30 won't have to leave OC too early. Any word of a caravan? Maybe Henri could lead the parade!

Sharon
 
An aside, I got the latest Clarks Spares catelog yesterday and noticed that he is reproducing the carb tags. He has the tags for my H4 AUC815's in stock /ubbthreads/images/graemlins/smile.gif

He would certianlly have any other SU parts you are looking for even if he is mainly an MGA guy.

www.clarkespares.com
 
We usually group up in South County. Last year we met in the Mervyn's/Denny's/DelTaco parking lot off the 5 at Alicia.

Don't have a plan yet this year but we usually head out then catch breakfast in SD.

I'll post the plan when we figure it out.

Henri, you coming? Anybody else out there wan'a caravan from OC?


PC.
 
/ubbthreads/images/graemlins/savewave.gif

Thank you Patton, I now have a spare set of Lucas Head lamps for the Daimler from CSR----Keoke /ubbthreads/images/graemlins/thumbsup.gif
 
Healey Gal, bout them washers,there weren't any there originally---Keoke /ubbthreads/images/graemlins/laugh.gif
 
I have no idea which screws you guys are talking about (since I have one of them new-fangled Jensen Healeys) but how about Loctite? /ubbthreads/images/graemlins/hammer.gif


PC.
 
No John, they can not be set up for left hand drive.However, in my case they are correct for the Daimler V8.But because you are only dealing with 45 watts on High Beam I doubt that the low beam RH Dip will cause a problem if used in the Healey.--FWIW---Keoke

Here is a tidbit,The correct {Left Hand Dip} Lucas Sealed Beam Headlamp for USA Is listed in the Jaguar Listing as Part # C20333 & C23640 there are others but not for USA just in case you want to source some. I have them in my Healey--Keoke
 
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