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77 esprit

Desperation

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Hi Folks,

Well I've finally reached the point of desperation with my S1 907. Some of you may know about my timing problem already. Some may not. Started when I had the alternator rebuilt. Re-installed the alternator. Pulled the belt up and onto the pulley. Started the car and ran it for a minute. When the warning light on the dash did not go out, I blipped the throttle. The engine stopped dead. No noise. No nothing. First thing I thought was the timing belt broke. Not the case. The alternator belt exploded because it had not properly seated on the crank pulley. Some of the drive belt must have jammed under the timing belt and forced it against a fixed part of the engine which shredded the edge of the timing belt. When I finally got the crank pulley off, I found about ten feet of what used to be the edge of the timing belt wrapped around the crank sprocket. It was so thick, the belt jammed and stopped the engine.

Began installing a new timing belt. Because I didin't know if there was any damage to the valve train or pistons, everything was moved in stages till I could re-established TDC. Using a long screw driver, I inserted it cylinder by cylinder moving the crank till it was roughly 90 degrees BTDC and all four pistons were roughly on the same plain. Once established, I moved each cam sprocket to the TDC position with the timing dot as indicated in the service manual. Set the ignition sprocket one tooth short of TDC. Installed the kind of new timing belt. Bought it ten years ago and never used it. Sat in its original shipping carton all these years. Really just wanted to install it to turn the engine over and then buy a new belt. Got everything back together. All the timing marks aligned. Turned the engine over by hand several times. Once I was sure there were no mechanical problems I then turned it over by the starter motor. Everything appears to work. Put the engine back together and tried to start it. NOTHING! The engine spins around freely. Doesn't fire. Doesn't do anything.

Rechecked the timing. Rechecked everything I could think of. The fuel pump runs. The float bowls are full. There is 12v at the low tension lead at the distributor. 12v at the points. There is spark at number one courtesy of my timing light. Checked the points. Gap set at .016 inches. The tappets depress and return against the cam lobes. Measured .011 inches clearance on all intake valves (supposed to be .005?). Everything else looks good. Haven't taken the exhaust cam cover off yet. Hasn't leaked in eight years. Will only take it off if absolutely necessary. In the end though, it won't fire and there is no smell of gasoline after turning it over for nearly a minute!

This morning I borrowed a compression tester. ZERO compression across all four cylinders!!!!! Tim E reminded me to be sure the throttles were wide open while spinning the engine. Still no compression. Going out to buy a leak down tester. Something is really wrong. I'm attaching several photos of my engine as it sits in the car right now. Everything is aligned according to the Lotus service manual. The front side of the cam sprockets are aligned with the intake / exhaust markings in their correct places according to page E 16 of the service manual.

Would some one please give me some new insight into what is going on. As the title says, I'm desparate!!! Thanks for your help.

Lyn

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I'd be whipping the exhaust cam cover off, whatever. You should get at least some compression, unless you have a valve bent on each cylinder. Inlet valve clearances are out, but not awful. That doesn't mean they ain't bent though. Can't remember from your previous thread if you established how far the cams were out at TDC.

Unless you've missed something simple, it looks like a cylinder head removal. :(

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Gary,

Don't understand what you mean by the cams being "out" at TDC. After I moved the crank to the 90 degrees BTDC position, there was less than one revolution counterclockwise of the cam sprockets to bring each of them to TDC. As I can only take so much disappointment in one day, I've put off buying the leak down tester till tomorrow. Thank you so much for answering. Every little bit of information helps :unworthy: !!!

Lyn

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Might sound stupid but are you sure the dissy isn't 180degrees out? That would still show as firing at TDC, just it would be the expulsion of the exhaust gasses TDC not compression of fuel & air TDC.

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Andy,

Great question. All I have to go by is the markings on the ignition sprocket. According to Lotus, the dimple is the ignition sprocket designation. There are two dots. One on either side of the dimple. One is supposed to be Red for European and Blue for Federal cars. My engine is timed with the dot on, what is in the attached page, the right of the dimple facing the center of the crank. The dots were supposed to be colored. Mine are all white. Just don't know how the timing can be out 180 as it is set. Then again, I'm not a mechanic. Don't even play one on TV. Do know just enough to get myself into serious trouble. Which I have done! Thanks for the suggestion. Really appreciate the extra effort.

Lyn

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Edited by 77 esprit

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The ignition sprocket could well be a long way out from where it originally was and the engine could well have been timed to a misaligned sprocket, happens a lot.

Turn your engine to the 10deg btdc and check the rotor arm is pointing to cylinder 1

Then check all the other leads are on the correct orientation if you've had them off as it's been known for people to put them on orientated clockwise forgetting that the dizzy is on the read of the sprocket and thus rotating anticlockwise as you look at it.

Don't panic just yet, your the second person in a couple of months to get a zero reading across all cylinders and theirs was a problem with the gauge not working with the engine as well.

Try the above and report back :)

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To verify everything is at TDC, check to see if #1 piston is at the top of it's stroke when you have everything else (cams, crank and dist.) aligned at TDC.

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Lyn, what I mean is, when you first encountered the problem, did you set the crank to TDC and check the position of the dots on the cam sprockets? If so, how far out were they? Too far and valves could be bent.

I agree with Andy ref timing, but if you set it up as per the diagram then that would imply you have it right.

No compression at all, even on a cold engine, is not good.

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Simon,

In answer to your questions:

Once I determined which dot to use for TDC, checked the location of the rotor. Assumed (perhaps a bad idea) the rotor was about to reach number one cylinder. Attached the plug wire for number one to that position then completed the firing order 1-3-4-2 counterclockwise as looking at the distributor from the bell housing. To complicate matters, I discovered at that point the wires were mis-marked. See attached photo. As the number four cylinder is the closest to the distributor cap, the wires are marked exactly backwards. Longest wire should be one. Shortest four. Oh well.

Checked the compression gauge with my air compressor. The gauge is fine. Put off buying a leak down tester today. Going to go over first thing in the morning and buy one. Then I'll pretty much know for sure what is going on without taking the head off. Want that only as a last resort. Thanks so much for your suggestions.

Gary,

Moved the cam sprockets less than one half revolution to bring them to TDC. My best guess is, if I had just left everything as it was, other than changing the timing belt, the timing would have been right on!

Lyn

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Edited by 77 esprit

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I'm a bit confused by something in your original posts. You say that you set the engine so all the pistons were level, i.e. half way up the bore. And then you set the cam pulleys at the TDC position. Then you put the belt on. Did you set the pistons to no.1 at TDC with the pulleys at the TDC position before putting on the belt? Otherwise the cams will be 90 degrees out.

Which cylinder are you taking to be number one? It is the one nearest the cockpit window, that is, the one at the front, furthest from the gearbox.

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I would try a second compression gauge to sure. You may not be getting a good seal.

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Lyn, I have a compression gauge if you want to use it to compare, but do you have an air compressor? If you do you could check for leakage by using the compression gauge hose into the compressor and just listening for hiss at on each cylinder at TDC on each. Autozone also loans some tools for free.

-Bob

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No smell of gasoline....hmmm...not sure about these cars, but the 82 Turbo has an inertia switch which turns off the fuel pump. This lives on the right rear wheel arch and has a red pip which sticks up when it's triggered....make sure this pip is pushed down, to start with...if the switch exists on your car. Then there's the other problem, which I fell foul of when my cambelt broke a week or so after I bought the car in 1988...the inertia switch has a plug in the bottom of it, which is very easily dislodged by your feet when grovelling in the back of the car!! Mine had been dislodged and, although everything was properly aligned and all the valve and ignition timings were spot on, it wouldn't run as the fuel pump wasn't working!! Worth a look in your case. For ignition timing, I'd go back to basic principles...establish no. 1 cylinder at TDC on the compression stroke....as you say, a screwdriver down the plughole will enable TDC to be exactly established, and checking the camshafts will show that the valves are closed, too, and thus the engine is on the compression stroke for no.1. Then pull the distributor cap and see where the rotor arm is pointing, and that's no. 1 cylinder. Put the rest of the leads back following the firing order, remembering the direction of rotation of the distributor. The wrongly marked plug leads make me suspicious...all sorts of things are possible....my brother did an engine swap on an Alfa Bertone GTV, 1300cc to 2000cc...and the new engine had had the distributor fitted 180 deg out. When he fitted the plug leads as the book said, of course, the engine wouldn't run....moving the plug leads about made it burst into life!!

As for the zero compression....if your gauge is working properly (try it on another car!) and you do have zero compression (and I've been there, too...) then you will most likely have done in a set of inlet or exhaust valves. The cambelt shredding itself can easily result in the camwheels jumping teeth and bye bye valves. I lunched a set of inlets on mine, once; you have to be sure you have enough belt tension and that the snubbers are adjusted correctly. However; from your descriptions I would say that you won't have caused the valves to bend, and your non running problem is to do with the ignition timing or the fuel supply. I suppose you are SURE there is fuel in the tank???!! Good luck...best to check everything before you start taking the engine apart.....if you do have to strip it; always easier with the engine out of the car......

Edited by molemot

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I'm a bit confused by something in your original posts. You say that you set the engine so all the pistons were level, i.e. half way up the bore. And then you set the cam pulleys at the TDC position. Then you put the belt on. Did you set the pistons to no.1 at TDC with the pulleys at the TDC position before putting on the belt? Otherwise the cams will be 90 degrees out.

Which cylinder are you taking to be number one? It is the one nearest the cockpit window, that is, the one at the front, furthest from the gearbox.

Trevor,

After the disaster, I wanted to move things safely. First moved the crank forward to a position (90* BTDC) where all the pistons were safely clear of the valves. Then moved the cam sprockets to TDC. Once I found the cams moved relatively free (spring compression), I moved the crank to TDC as seen on the flywheel. As you can see from the photos, all four timing marks align which can only happen if everything is set correctly. The ignition sprocket was aligned to the crank by first painting a mark on the sprocket. Then stuck a length of string to the crank bolt head and streched it up to the ignition sprocket. Aligned the mark on the sprocket to the string. That is dead on. I'm completely sure the timing sequence is good. Also the photos show the positions of the intake valves as well as the timing marks on the sprockets. Again that can only happen if the timing is correct. The number one cylinder is closest to the timing belt. Incidentally, the cam timing sprocket markings were actually set from the front of the engine as seen from the window. Once in position, the entire system matches the diagram on page E 16.

So many of you have suggested the fuel system may actually be at fault. Don't smell gasoline at all even after spinning the engine for nearly a minute. Going to take the CD 175's apart again today and re-check them. First is buying a leak down tester and eliminating (hopefully) that possibility. Thanks again for your suggestions.

Lyn

No smell of gasoline....hmmm...not sure about these cars, but the 82 Turbo has an inertia switch which turns off the fuel pump. This lives on the right rear wheel arch and has a red pip which sticks up when it's triggered....make sure this pip is pushed down, to start with...if the switch exists on your car. Then there's the other problem, which I fell foul of when my cambelt broke a week or so after I bought the car in 1988...the inertia switch has a plug in the bottom of it, which is very easily dislodged by your feet when grovelling in the back of the car!! Mine had been dislodged and, although everything was properly aligned and all the valve and ignition timings were spot on, it wouldn't run as the fuel pump wasn't working!! Worth a look in your case. For ignition timing, I'd go back to basic principles...establish no. 1 cylinder at TDC on the compression stroke....as you say, a screwdriver down the plughole will enable TDC to be exactly established, and checking the camshafts will show that the valves are closed, too, and thus the engine is on the compression stroke for no.1. Then pull the distributor cap and see where the rotor arm is pointing, and that's no. 1 cylinder. Put the rest of the leads back following the firing order, remembering the direction of rotation of the distributor. The wrongly marked plug leads make me suspicious...all sorts of things are possible....my brother did an engine swap on an Alfa Bertone GTV, 1300cc to 2000cc...and the new engine had had the distributor fitted 180 deg out. When he fitted the plug leads as the book said, of course, the engine wouldn't run....moving the plug leads about made it burst into life!!

As for the zero compression....if your gauge is working properly (try it on another car!) and you do have zero compression (and I've been there, too...) then you will most likely have done in a set of inlet or exhaust valves. The cambelt shredding itself can easily result in the camwheels jumping teeth and bye bye valves. I lunched a set of inlets on mine, once; you have to be sure you have enough belt tension and that the snubbers are adjusted correctly. However; from your descriptions I would say that you won't have caused the valves to bend, and your non running problem is to do with the ignition timing or the fuel supply. I suppose you are SURE there is fuel in the tank???!! Good luck...best to check everything before you start taking the engine apart.....if you do have to strip it; always easier with the engine out of the car......

John,

If you tap the side of the rear carburetor with a rubber mallet, the fuel pump ticks a few times. Also took the float bowl off the rear carb. It was full of fuel. Against better advice, I have a clear fuel filter in the engine compartment. You can see fuel flowing in the filter when the pump runs. The problem of not smelling gasoline is perplexing. Suppose the jets could be blocked by "crud" in the fuel. At this point, most anything in the carbs could be at fault. Right after this happened, noticed some "crud" between the opening of the intake manifold and the throttle plates of the carbs. Not a lot but sort of "gritty". Cleaned it off. Has not reappeared since. Possible it got into the jets. Yep, clean the carbs. First though is a leak down.

Lyn

Lyn, I have a compression gauge if you want to use it to compare, but do you have an air compressor? If you do you could check for leakage by using the compression gauge hose into the compressor and just listening for hiss at on each cylinder at TDC on each. Autozone also loans some tools for free.

-Bob

Bob,

Great idea. Same fittings as my air compressor. I can regulate the output down to 80 or 90 PSI. I'll try that first before buying the tester. Thanks.

Lyn

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Lyn,

I f you are 100% sure that the cams and crank are timed correct you should be getting some kind of compression readings. Lack of compression in all four cylinders and no fuel being drawn into the cylinders unfortunately starts pointing to valve damage. Double check everything again and be 1000% sure the cams and crank are timed correctly. Do a compression test again using a different gauge. If you achieve the same results, zero compression, then unfortunately it looks like the only remaining option is to remove the head for physical inspection.

If you had compression we could rule out valve damage and start to look at the fuel system and the ignition system. But there is no point moving on to those systems if the engine registers no compression.

Edited by GavinS1

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OK Guys,

Unless someone can tell me there is something wrong with the timing on cylinder one as shown in the above photo, I have sixteen slightly bent valves. Guess it doesn't matter whether they are slightly or terribly bent. They are all bent. Tried to use Bob's idea of the compression tester to do a simple leak down. Forgot about the one way valve. Didn't work. Bought a leak down tester from Harbor Freight ($40). 100 percent leak down in all cylinders. Surprisingly, no leaks past the rings! All air pressure losses are through the valves stuck open intake and exhaust. Going to start tearing the top side of the engine off. Slowly but surely and mark everything that comes off.

Really, really appreciate everything you folks have done to try to help me. Knew it just couldn't be that easy :cry: . Only other thing I need from my friends. Who would you trust to rebuild the head in the United States? With UPS and Fed Ex Ground available, location is not as important as being able to trust the mechanic. Thanks again.

Lyn

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To get leak on all cylinders you'd not need all 16 to be bent, so don't assume the worst. Even if all cylinders leak due to bent valves it's more likely to just be on either the exjaust or inlet, for two cylinders not both, then the opposite side for the other two. Don't asume they are bent yet.

Use the leakdown tester. Turn the engine over to the point at which the valves should be closed, take cam covers off and look for the point at which both inlet and exhaust are moving (one set closing/ just closed one set opening/ about to start opening), add the compressed air and check where it leaks to. Does it come out of the exhaust, does it come out of the carb/ inlets, does it come up the valve stem?

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Lyn,

Give Harry a call at Viking

clicky to Viking

See what he suggests. They have done lotus of work on 9XX engines and have an excellent reputation.

Tim E maybe able to recommend a shop more local.

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To get leak on all cylinders you'd not need all 16 to be bent, so don't assume the worst. Even if all cylinders leak due to bent valves it's more likely to just be on either the exjaust or inlet, for two cylinders not both, then the opposite side for the other two. Don't asume they are bent yet.

Use the leakdown tester. Turn the engine over to the point at which the valves should be closed, take cam covers off and look for the point at which both inlet and exhaust are moving (one set closing/ just closed one set opening/ about to start opening), add the compressed air and check where it leaks to. Does it come out of the exhaust, does it come out of the carb/ inlets, does it come up the valve stem?

Andy,

Comes out both the intake manifold through the carbs and the exhaust pipe. Nothing from the crankcase breather so the rings appear to be OK. Started with number one in TDC. Moved the cams to number three. Then number four and finally number two. Checked to see that each cylinder had both the intake and exhaust valves closed before trying the leak down. Had to guess at the absolute location of each cylinder as the cams rotated through 360 degrees. Put a mark on the bearing carriers between cylinders. Knew approximately where the intake cam lobes should be for each cylinder compared to number one at TDC. Pretty sure I got it right! That way, both the intake and exhaust valves should be closed if everything was OK cylinder by cylinder. I'm more than willing to redo the test if you think I may have done it wrong. Not a street car mechanic. Know just enough to get myself into serious problems.

Lyn

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Lyn,

How about Lee Johnson at Esprit Motorsports down the road from you in Elmira/Corning area? See http://www.rustdepot.com/Esprit%20Performance/Esprit%20Performance.htm and his TLF profile is at http://www.thelotusforums.com/forums/index.php/user/1133-esprit-aviation/

- Matt

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Andy,

Comes out both the intake manifold through the carbs and the exhaust pipe. Nothing from the crankcase breather so the rings appear to be OK. Started with number one in TDC. Moved the cams to number three. Then number four and finally number two. Checked to see that each cylinder had both the intake and exhaust valves closed before trying the leak down. Had to guess at the absolute location of each cylinder as the cams rotated through 360 degrees. Put a mark on the bearing carriers between cylinders. Knew approximately where the intake cam lobes should be for each cylinder compared to number one at TDC. Pretty sure I got it right! That way, both the intake and exhaust valves should be closed if everything was OK cylinder by cylinder. I'm more than willing to redo the test if you think I may have done it wrong. Not a street car mechanic. Know just enough to get myself into serious problems.

Lyn

That sounds like you've done what you need to.

Ona more positive note, when we pulled SimonF's Turbo esprit apart we could only find damage to one pistone (& rings) which was the cylinder showing nearly 100% leak but one had a similar lead-down result of 85%, we can only take that have been a valve shim issue.

So don't assume things will be horrendous.

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If you are not too worried about keeping your original head and want to keep cost down,

how about this?

http://cgi.ebay.co.uk/Lotus-907-cylinder-head-Esprit-Eclat-Elite-Sunbeam-/290576372399?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43a7b392af

If nothing else it could be a source of replacement valves?

I know its for sale in the UK but.....

Are you near New Jersey? my son is visiting NJ in July and could bring it / the valves out and then you could arrange intra US shipment?

John

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If you are not too worried about keeping your original head and want to keep cost down,

how about this?

http://cgi.ebay.co.uk/Lotus-907-cylinder-head-Esprit-Eclat-Elite-Sunbeam-/290576372399?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43a7b392af

If nothing else it could be a source of replacement valves?

I know its for sale in the UK but.....

Are you near New Jersey? my son is visiting NJ in July and could bring it / the valves out and then you could arrange intra US shipment?

John

John,

Thank you so much for your kind offer. It appears the machine shop recommended by Tony Vaccaro is only thirty or so miles from my house. That guy just rebuilt a friends Elan Sprint engine and did a great job very reasonably. He has evidently earned the trust of my fellow Lotus Owners Of New York (LOONY) members. Really would like to keep all the numbers matching if possible. One of the reasons I still own my Esprit after thirty four years is fellow owners like you :unworthy: .

Incidentally, where I am in New York State is, at the minimum, six hours to the Northern most point in New Jersey. Central Jersey is roughly eight hours away.

Lyn

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Lyn: This may be a dumb question - but I see from your first photo of the timing belt that the dots are aligned on the sprockets. However, I use the dots on the other side of the sprockets - the side that faces the bulkhead - need a mirror to see them.

The manual's diagram of the proper alignment of dots is viewed from the front of the engine. Are the dots on the front side and the back side the same location? Could be.

Bob

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Bob, great spot. The dots are in different places, that's their purpose, Inlet timing one side exhaust timing th other and that could lead to valves leaving no point with both sets closed near TDC.

Edited by andydclements

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