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Discussion Starter #1 (Edited)
Well, the sucker finally started up and is firing on all 4 cylinders :D

I did a lame attempt at tuning the carbs (they were completely off, not sure whether the tune was off, or the carb is still clogged requiring a changed tune, either way this is temporary).

Anyways, my short term goal right now is to get it running enough so I can drive it to somewhere where they can service/tune the carbs. Currently the car will move, I can drive (albeit with enough noise of intake and exhaust backfires), however the problem right now is some serious smoke that makes it impossible to drive around without causing an accident or a ticket :lol: .

Any suggestions for this:?

-White smoke, always. There's a constant stream of white smoke that comes out the tailpipe, increases in thickness as the revs go higher, thick and white. The coolant level hasn't changed (no leaks), and the tank was emptied and refilled with gas, so there shouldn't be water.
-Blue smoke, sometimes. Sometimes appears, especially when you shift, or get to higher rpms. A compression test shows all cylinders at 165-175PSI

Valve timing is spot on, ignition timing is close enough for now (no strobe, and no points, but the crank mark was aligned close enough for when the rotor would pass).

Note: There is some seafoam in the gas (although I was under the assumption a low dosage (1/3 can) wouldn't cause all the smoke), and some in the oil (to be changed soon). However not sure where oil would leak in since compression is fine.

Thoughts?

Edit: Somehow I forgot to ask this important question too haha, here's another issue:

The engine idles really weird. It idles at about 700, but sometimes seems to 'catch' and progressively idle faster and faster until around 2000, then randomly fall back down. The throttle isn't sticking, nor are the butterfly valves as far as I can tell. You can also do this by engaging the choke, it'll be idling at maybe 700, then you pull out the choke cable and the idle shoots up....

What the hell did I mess up while 'fixing' the carbs?
 

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I'm certainly not a mechanic, but I think blue smoke tells of burning oil, especially as you say it gets worse at higher revs. White smoke could be burning brake fluid - has that level gone down at all in the reservoir - maybe a servo leak? If it's not white smoke but steam, then it sounds like water vapour.

Someone who really knows will be along soon! :cheese:
 
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Hello,

Best thing to do is to narrow down the cause of the smoke by elimination.

DOes your car smoke only when driving or also when stopped?
When I bought my spider the servo rubber were dead. Resulting to a hugh amount of white smoke with a nasty smell.
Break fuilde level?
What is the smell like? engine oil and brake liquid doesn't smell the same when it burns.

Maybe the piston ring are failing, so check engine oil level...

Then if the car didn't run for long there might be some humidity along the exhaust so you might want to let the engine for a bit longer.

Water tank, look at the coolant is there any traces of oil.

Last but not least you said that your carbs are not properly tuned.
If your mixt is very rich it might be a cause too.

So have a good snif at your exhaust, check all your level before and after running the car for a little while.
I am not a mecanic either, just trying to help.

Good luck

Andre
 

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If you have a rubber pipe from the servo to the inlet manifold you could try taking the pipe off the servo and blocking the end. Used a sparkplug insulator end for this. See if this stops some of the smoke. Obviously you would have very little brakes so perhaps don't take it on the road like this.
 

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Discussion Starter #7 (Edited)
Hello,

Best thing to do is to narrow down the cause of the smoke by elimination.

DOes your car smoke only when driving or also when stopped?
When I bought my spider the servo rubber were dead. Resulting to a hugh amount of white smoke with a nasty smell.
Break fuilde level?
What is the smell like? engine oil and brake liquid doesn't smell the same when it burns.

Maybe the piston ring are failing, so check engine oil level...

Then if the car didn't run for long there might be some humidity along the exhaust so you might want to let the engine for a bit longer.

Water tank, look at the coolant is there any traces of oil.

Last but not least you said that your carbs are not properly tuned.
If your mixt is very rich it might be a cause too.

So have a good snif at your exhaust, check all your level before and after running the car for a little while.
I am not a mecanic either, just trying to help.

Good luck

Andre
Only when driving. When idling it's not smoking. Smells...just bad, not really sure what it smells like, sorry.

Oil level is fine, compression test shows all cylinders at ~170. Coolant is clean, oil is clean of coolant, brake level is alright.

Sorry for the noob question, but where is the servo/servo rubber?

If you have a rubber pipe from the servo to the inlet manifold you could try taking the pipe off the servo and blocking the end. Used a sparkplug insulator end for this. See if this stops some of the smoke. Obviously you would have very little brakes so perhaps don't take it on the road like this.
Only happens when running, so I'd rather not drive around without brakes :p

Bad news too, cyl 4 stopped working apparently. It backfires a lot (the others stopped after some tightening onto the manifold, idle tuning, etc.), but now cyl 4 is just spitting back out, and isn't doing anything (pull the plug, no difference. There's spark, compression, and it sure as hell is spitting back a fuel/air mixture :/)

Wits end. Especially since I leave for school in about 12 days. I guess if I don't find it soon it's a next summer car again.

:cry:

Edit: I still don't get the blue smoke either. Compression test shows fine and the oil level doesn't seem to change, yet there's blue...
 

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If you tightened the inlet manifold and improved it a bit does that suggest the inlet manifold gasket is partly missing? We used to prove this sometimes by wiping some thick grease along the join where the inlet manifold gasket is, hopefully reducing the air drawn in.
 
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Hello,


Ok then I might be the diaphragm of the break servo.
See the pictures join (if it works) otherwise just google servo bendix...

You should then get the diaphragm change (servo kit), brake line bled, and you should be back on the road.

I hope I am right, since it is quite simple to get it sorted.

Cheers

ANdre
 

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Hi,

Sorry I forgot your 4 th cylinder issue...

Once again I am not a specialist, but you were saying that your carbs are not tunned properly. Spitting petrol out is often a poor mix result.

How s your ignition point? Spark plug?

Maybe your carbs are dirty...

Good luck

Andre
 

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Only happens when running, so I'd rather not drive around without brakes :p
It isn't that the brakes stop working but the power assistance that makes life easier is gone. You'll find that you need a lot more pressure on the pedal to get the same stopping effect. I had unassisted brakes on my Mustang and have driven a race tuned E type on a track without boosted brakes. It just takes a bit of getting used to.
 

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Bad news too, cyl 4 stopped working apparently. It backfires a lot (the others stopped after some tightening onto the manifold, idle tuning, etc.), but now cyl 4 is just spitting back out, and isn't doing anything (pull the plug, no difference. There's spark, compression, and it sure as hell is spitting back a fuel/air mixture :/)
You may have some sort of fuel/air mixture on number 4 but it has to be the correct ratio for it to fire. Given that cylinder 4 is the take off point for the brake servo I would consider this to be the first area for investigation.

If you are serious about getting to know your Webers and keeping them in tune then I strongly recommend Pat Braden's book "Weber Carburetors", getting a 4 way vacuum balance gauge (very good at showing air leaks on specific cylinders) and a Colortune (excellent for setting the correct mixture).

I had a lot of problems with carbs spitting and cylinders not firing and it came down to a combination of all the things discussed: The brake servo hose was leaking, the gaskets for the carb mounts were missing! and the rubber carb mounts themselves were cracked. You won't be able to tune the carbs at all well until you have addressed these issues.
 

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Discussion Starter #13
Hi,

Sorry I forgot your 4 th cylinder issue...

Once again I am not a specialist, but you were saying that your carbs are not tunned properly. Spitting petrol out is often a poor mix result.

How s your ignition point? Spark plug?

Maybe your carbs are dirty...

Good luck

Andre
I'll get someone who knows what they're doing to set the mixture today I think. Carbs are pretty clean, sparks are good, points are good (and afaik the timing is good, I played with the cap a little and it didn't fix anything, if anything it worsened it, so I put it back).

You may have some sort of fuel/air mixture on number 4 but it has to be the correct ratio for it to fire. Given that cylinder 4 is the take off point for the brake servo I would consider this to be the first area for investigation.

If you are serious about getting to know your Webers and keeping them in tune then I strongly recommend Pat Braden's book "Weber Carburetors", getting a 4 way vacuum balance gauge (very good at showing air leaks on specific cylinders) and a Colortune (excellent for setting the correct mixture).

I had a lot of problems with carbs spitting and cylinders not firing and it came down to a combination of all the things discussed: The brake servo hose was leaking, the gaskets for the carb mounts were missing! and the rubber carb mounts themselves were cracked. You won't be able to tune the carbs at all well until you have addressed these issues.
I'll check out those things you mentioned.

Sorry again, but where exactly is the brake servo, and what am I disconnecting?
 

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Sorry again, but where exactly is the brake servo, and what am I disconnecting?
The brake servo is the cake tin size cylinder on the LHS of the firewall. There should be a thickish hose connecting it to the back of the engine block.

First off, remove the hose and check that it isn't perished - probably worth replacing anyway if it doesn't look new. Any automotive hose of the correct size should do as long it is resistant to petrol.

Then try plugging the hole in the back of the block. The easiest way is to connect up the hose then put a suitable bung in the free end of the hose.

Now can you get a decent mixture setting on number 4? But remember, there is a good chance that this isn't the only thing wrong. I have another, smaller vacuum hose connecting the front of the manifold to the top of the cam cover - more scope for leakage there.

Also try gently raising and lowering the carbs to slightly flex the rubber mountings. If the mountings have perished the engine note will change as you open and close the cracks. Another test is to spray the manifold areas with a shot of carb cleaner. If there is a leak the carb cleaner will upset the mixture balance and the engine note will change slightly.

Good luck :thumbs:
 

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Discussion Starter #15
The brake servo is the cake tin size cylinder on the LHS of the firewall. There should be a thickish hose connecting it to the back of the engine block.

First off, remove the hose and check that it isn't perished - probably worth replacing anyway if it doesn't look new. Any automotive hose of the correct size should do as long it is resistant to petrol.

Then try plugging the hole in the back of the block. The easiest way is to connect up the hose then put a suitable bung in the free end of the hose.

Now can you get a decent mixture setting on number 4? But remember, there is a good chance that this isn't the only thing wrong. I have another, smaller vacuum hose connecting the front of the manifold to the top of the cam cover - more scope for leakage there.

Also try gently raising and lowering the carbs to slightly flex the rubber mountings. If the mountings have perished the engine note will change as you open and close the cracks. Another test is to spray the manifold areas with a shot of carb cleaner. If there is a leak the carb cleaner will upset the mixture balance and the engine note will change slightly.

Good luck :thumbs:
Thanks man. Will try all this stuff. Unfortunately some seal completely went, and it's tons of blue smoke now. As well, I noticed a slight drop in coolant level. Sigh. So gasket replacements I guess first thing before I worry about cyl 4 problems. (brake fluid still hasn't changed thank god).

What sort of gaskets will need to be bought for this job? Cyl head, probably cam cover (it's not in the best of shape), manifold gaskets...what seals the valves keeping the oil out of the cylinders? The weird thing is compression tests show fine, but there's obviously oil be burned some how.

(I might note, one weird thing is that there is no chocolate milk oil or anything indicating the oil and coolant is mixing, just the white and blue smoke and dropping levels now..)
 

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Well it sounds like you have more to worry about than a bit of carb tuning! Sorry :(

If you want to dive in then you should buy a full head gasket set which will include all the inlet/exhaust manifold gaskets, cam cover gasket, valve seals etc. as well as the head gasket, about 40 quid in all. Get a Reinz set if you can.

The next step-up from a compression test is a leakdown test which will tell you/us a bit more. But it may be that you'll have to have the head off to know for sure what is going on.

But don't despair yet, follow up on the carb stuff first.
 
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