Re-starting The Tc

ok – if you have spark fuel and timing try adjusting the two rich idle screws 1 and 1/4 turns out from the bottom------the compression on my elan tc is 180 and on the 7 tc 175 ed law

My +2130s has simlar figures

Matt,
A car that sat for 13 years and was not stored properly is going to have at least gum deposits left in the fuel system when the fuel went sour. The carbies undoubtably need cleaning but be careful how it’s done. Go buy the proper dunking type cleaner to do the job. When you do this the leather seals on the throttle shafts will be need to be renewed. The leather will have dryed up and the chances of it sealing properly are nearly zero anyway. Since new Webers are now not available but the spares still are your options are limited. You must rebuild yours or find good used units to buy. If you’re mechanically gifted then I’d say go for the rebuild option though it gets quite expensive to DIY. Otherwise seek out qualified help by calling the folks at Webcon UK for advice. If there is thick corrosion in the bottoms of the float bowls then in the past they would have be considered destroyed but in light of the fact there are no new Webers being made anymore perhaps that’s not the case anymore. Unless of course the metal has crumbled away to the point the structure is damaged like some threads are gone.

Don’t buy the Weber leather seals because they are junk. About half of them will have holes from the way they where poorly cutout of the sheet. Make up your own and saturate them with Mink or Neatsfoot Oil. To tell for sure whether or not the leather seals are toast there is a simple test to perform. Good seals will allow the engine idle speed to slow down to around 400 rpm where the engine will stall out as the idle speed screw is slowly back off. If the engine merrily idles along inspite of the idle speed screw being moved then it’s doing so on the airleaks. So what you say? Well if enough air is getting sucked in by way of the throttle shafts then it isn’t being forced to flow past the first progressive hole so when the throttle shaft gets opened ever so slightly there will be a stumble off idle that cannot be tuned away. Guessing the leather seals are only good for about five years even if the car is seldom driven.

AND have a well equipped machine shop then go for it.

Thanks again fellas. My pressure gauge was posted today, so that could be a job for the weekend. The pressure test is easily done and will hopefully, hopefully eliminate poor compression as a problem.

The carbs seem in quite good condition. The car itself was dry stored for all that time but actually went into storage in working order - the previous owner stopped using it only 'cos his house burnt down which made him both very busy and very broke. The carbs, amazingly, had no sludge or gunk in them when I opened them up and there is no visible corrosion on either the inside or outside. However, I already know the top seals don’t as I had an overflow issue earlier; now resolved.

If the pressure test reveals nothing, I’ll try the idle screws as suggested by twincamman. If that gets me nowhere, the carbs will go back on the bench for a strip down and refurb. I’d prefer that than engine rebuilds!

Check to see if the accelerator pumps are working. If they do then you can get it to run by continuing to juice it with petrol via the pumps alone. You can check that they are working in situ with a mirror by looking down the throat the of carbie and quickly open the throttles with the engine switched off. You should see it squirt out a stream of fuel directed towards the throttle plates in every throat. If it does not squirt properly on every cylinder them report that back and I’ll describe how to possibly fix it.

What flavour of Weber are these? It’s last two digits (XX) of the label 40DCOE XX.

BTW, trying to keep the fuel from leaking out using the paper gaskets from under the top cover and the inspection cap for the jets is hopeless. The newer carbies 151/2 have an elastomer gasket which does the trick great with a slight modification. The ones to seal the inspection cap I made up. I posted how to do it here sometime ago so search for it.

give some thought to replacing the points or at least cleaning the points up and re gapping them----25 years may have caused some corrosion------i replaced the coil on mine after it had been stored for many years – it had many of the same problems you describe and it ran a treat – I used a big blue Bosch coil instead of a Lucas— ed law

Hi Ed, the TC is now a points-free zone after I upgraded to the Aldon Ignitor, also with a new Lucas Gold coil. I’m pretty sure it all works and is statically timed as I’ve been through it all a few times.

Keith, thanks for the tip about the accelerator pumps, I’ll try that on Saturday afternoon when I can next get my hands dirty. A few posts ago, you mentioned about air getting in, and I think that may be a factor, IF the screws for the idle jet and mixture need to be air tight. I just took a look at their rubber seals and they are shot! Forgive my lack of understanding, but is that a problem?

Matt

Yes, airleaks are bad. Small ones are not the problem at the moment but any that are large will cause that cylinder to not fire. For now just goober some grease over the suspected leaking o-rings to seal them temporarily and get the engine to fire up and run smoothly. Smear lots of grease over the ends of the throttle shafts to seal up the leather shaft seals also. You can fix those small problems later. Don’t lose focus which is just to get the engine to run first.

The compression test is necessary because there is a good chance the piston rings are frozen from corrosion or the exhaust valves might be burnt on #1 & 2 cylinders. Another fault condition which most people don’t consider is at least two valves sat with their springs fully compressed for 13 years. One intake and one exhaust. Springs when highly stressed will relax slowly over time. Get it running for now but for sure you’re looking at the very least having to remove the head to put a new set of valve springs in it. If you don’t it will run like crap at high rpms and you’ll never figure out why it’s always missing or if not fully missing then it lays over and does not pull hard. For this reason our BRM race engine has the crankshaft rotated to another position at least once a month to slowdown the degradation process.

That’s not so bad. Had dinner with Dan Davis the editor of VictoryLane magazine about ten years and he led into the a discussion about valve springs by asking me to guess how much a set cost for a Ford DXF engine. I guessed right on the nose at $2400. He found out the hard way those engines have to be rotated weekly and the springs are toast after one year even if it does not get fired up once. Vintage F1 cars cost $500 per lap to operate I’m reliably told as of ten years ago. Little wonder it’s done with pneumatics now.

Here’s the original Weber manual but the part you want to pay particular attention to is the Running Fault section which starts on page 27.
weber.pdf (2.0 MB)

Matt,
Keep in mind there are some glaring omissions from the Running Fault list. Like checking for the leather seals on the throttle shafts having shrivelled and become stone hard. Also the fact the process to correctly phase the throttle plates relative to the first progressive hole on the micron level would be so prohibitively expensive for the OEM to do on each engine likely it was not done at all. Why they left mentioning the compression test off their list is a bit of a mystery though.

The manual states the compression reading should be at least 160 psi with no more then a 20 psi variation.

The compression test revealed the following:
Cyl 1 = 180psi
Cyl 2 = 175psi
Cyl 3 = 180psi
Cyl 4 = 180psi
I’m guessing that 180psi isn’t ‘too much’ if the manual states ‘at least’ 160psi. I think its time for the carb refurb… Actually, I suspect this will just be the cleaning and seal replacement exercise refered to in the manual. Blowing out and reseating the jets will at least confirm there are no blockages.

Just to put this into persepctive, when I say my carbys look in good nick (externally), take a look here:
http://www.northamptonmotorsport.com/default.asp?id=19
The first 2 shots on that page show a really mucky Weber. Mine genuinely look more like the one in the 3rd picture (ie refurbed and finished) with the exception that my brass bits don’t gleam!

Permission granted to tear away! :smiley: Are all the accelerator pumps working and were you able to get it started though? You are feeding it fresh petrol and not 13 year old stuff correct? :ph34r:

Just because they look grungy does not mean they are broken. Their age is probable cause though.

Sorry I’ve been quiet for a few days, been a tad off-colour so haven’t had chance to spanner the car. No, the accelerator pumps don’t seem to work, but yes I am using new petrol. The 13 year old 4-star has been drained and is now on cleaning duties. Thanks for the link to the Weber manual. I think the plan is to remove the carbs again, do a full bench service and re-seal and then try to get her fired up again. Although I could see no evidence of blockages when I was cleaning them, I do think that the internals have gone dry and gotten stuck - hence the accelerator pump not working. I’ll report back when they are re-fitted; thanks for your help.

IIRC, there’s a check valve consisting of a ball bearing and a slug above it to weight it down to allow the accelerator pump to gulp fuel in each of the throats. They are either stuck open or closed but they are stuck for sure. Don’t bother taking the carbies off the car to just fix that problem. It’s only about twenty minutes effort to pull the covers off and correct that condition. While the top cover is off you can test the accelerator pumps for proper functioning. Just be careful because the round plate holding down the spring on the accelerator pump pistons can pop up out of place. Once those squirt okay you should be able to fire it up okay.

Go to page 14 of the Weber Manual and the check valve is shown there as an exploded assembly. It’s on the lefthand side with a screwdriver hovering above it. Piece of cake!

Hi

On my carbs that had been sitting both accelerator pumps were jammed. I pulled and wiggled them quite vigourously before they came free. If you are tugging at them and bending over the carb you risk petrol in the face when they let go.

By the way, I read that the valve springs that were compressed while the engine was sitting (if not turned over regularly) will be junk after so many years. Also the piston rings can indent the bores (apparently). My engine sat for 5 years so it is probably true of mine as well. I always turned my other TC engines over when they were sitting. I thought that it was to push the oil around. Obviously there are other benefits as well.

All the best

Berni

Hi Berni,
They don’t indent the engine bore but what normally does happen is since two valves are open there is a way for humidty to enter into the cylinder. The rings are cast iron or steel and the pistons are aluminum. When the two metals are close together they can corrode. Not sure if it’s galvanic or not. I’ve got the ASM Corrosion Handbook sitting in front me of but it weighs at least ten pounds and is a pain to navigate through and I’m lazy so I can’t say for sure. :rolleyes:

That’s why I told Matt to do a compression test. If they are stuck the engine will not have much in the way of compression. He was lucky to have it all be free and come right up to full compression. My engine sat for twenty-five years and it was frozen completely solid from the corrosion of the rings to the cylinders walls and the pistons.

have you tried new plugs and wires ?? if the plugs were wet [I believe somewhere in this epic struggle] that was reported ed law :wink: ----

Epic the struggle may be, but it consists of only a few hours each weekend and the odd evening, which means its dragging on a little, but not consuming my life. Yet.

Progess, of sorts…

Took off the top covers and removed, cleaned and refitted all of the jets. Took the accelerator pumps out, freed the balls, cleaned and returned them. WD40 certainly put in an appearance. Put it all back together and on the first crank it fired for a second or so. An improvement certainly. Then I was able to get it fired quite a few times, but it fizzled out every time. After careful study of what was going on, I can tell you the following:

  • it would start only with the choke and zero accelerator.
  • it would run only on pots 3 and 4. 1 and 2 were not firing at all.
  • once running, 3 and 4 could keep it going for about 6 seconds before fizzling out.
  • any attempt to drop the choke caused a fizzle out.
  • any attempt to add accelerator caused instant stop.
  • accelerator pumps still don’t work!

I count this as a progression from not firing at all, so am not frustrated. Yet… <_<

have you replaced the 8 rubber ‘o’ rings between the carbs and block on the spacers? It still sounds like fouled plugs or an intake leak ----do not over tighten the carbs or you will break the ear mountings[ I’m assuming its a Webber head ] --you may go back to a points system until the lump runs and then put the hi tech system back in----I personally don’t mind points as the motor is not hard on them -when it runs so sporadicly it suggests a distributor problem to me -----set the static timing and see if #1 is the correct position in the distributor cap and spark the plug by turning the distributor —then count 1342 – ed-----