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Motor Dies - will this never end?  Rating:  Rating
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 Posted: 10-11-2005 04:15 pm
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Joel
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One of these days I'll actually be DRIVING this car instead of sitting alongside the road w/ it. . .

Interesting problem. I think it's temperature dependent but I'm not sure. I'm driving along and the motor simply dies - stopped, kerplooey, kaput. Cranks fine, lights work, everything seemed ok. It just won't fire.

After fiddling around a bit - she cranked right back up. I go another 5 blocks or so and - completely dies again. I let her cool down (not running hot mind you - the guage was just barely starting to move up) and she starts right up. Yep, you guessed it - another 10 blocks and it happens again.

I'm pretty sure it's electrical as it IMMEDIATELY dies. No sputtering, puttering or hesitation - just bang - it's dead.

This just happened last nite. Fortunately, I was only a couple of blocks from home. I haven't messed around with it yet to see if I can make it happen again. The interesting thing is that I drove it last week probably 30+ miles on a little jaunt and had no problems. It did cut out one time (same as described above) but it started right up and ran no problem.

Any ideas? I'm thinking there must be some temperature dependent switch I need to check on. I just haven't had time to think about it yet.

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 Posted: 10-11-2005 05:22 pm
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Mark Rosenbaum
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As you note, this is probably an electrical problem.  In the whole car, about the only things temperature dependent are the sensor for the temp gauge, and the temp compensators on the carburetors (assuming Strombergs), and neither of these is likely to be able to cause the engine to shut down instantly.

I suggest examining the various wiring connectors between the distributor and the ignition switch.  Probably you'll find either a corroded pin or socket, a broken wire that just happens to be making contact with its connector, or something similar.  If that doesn't help, check the points gap (assuming points), the flex wire (points to coil terminal) inside the distributor (again assuming points), and the ground wire between fixed and moving plates.  If that doesn't help, try substituting the ignition coil.

 

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 Posted: 10-11-2005 06:22 pm
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John Kimbrough
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I know it sounds like an electrical problem, but make sure your fuel filter is not plugged.  Mine acted like this because the pump was straining to get fuel to the carbs.  After sitting a couple of minutes, enough got through that it would refire and run for a few minutes, then repeat.  John.

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 Posted: 10-11-2005 09:38 pm
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Joel
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fuel filter is on the 'to check' list as well. but it stops so suddenly i wonder if that's it. but, it vill be checked.

tks!

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 Posted: 10-12-2005 03:57 pm
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Judson Manning
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Joel,

It's either fire or gas.

Power goes from the battery, to the key, to the tach, to the coil, to the distributor.  If anything in this chain breaks the tach will IMMEDIATELY drop to zero.  The problem is electrical.  There is a lose wire/connection that you should be able to track down fairly easily.

If instead the tach skips, fumbles and drops with engine RPM as it dies, the problem isn't electrical, it's fuel. 

What I hear you describing is a faltering fuel pump that only quits when you put the car in gear!  I had two of them... 

Alternatively, a fuel float could be stuck or the gross jets could be clogged in one or both carbs causing an over-lean condition.

Judson

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 Posted: 10-12-2005 03:58 pm
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Brett Gibson JH5 20497
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Sounds electrical to me, ( but always good to run with clean filters), have you checked your battery and ground connections, you may have power but without a good ground you dont have a complete circuit.

also as an after thought, is your fuel pump clicking all the time during the failure ....................  

Brett.

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 Posted: 10-13-2005 08:33 pm
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Joel
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Ok, my fuel filters were in BAD shape. So I swapped them out. I drove around for 1/2 hour or so (all within a few blocks of home in case I need to push it back. . .) and it didn't die out. But, I'm still not convinced that was the problem. We'll see.

An interesting aside. After I got the filters changed and started back up again, the car had a really interesting spat of revving up and down between 0 and 2500-3000 rpm for a minute or two. Very odd as there certainly isn't any computer to go awry.

Now, my idle is up about 1-200rpms from where it was before. I suppose that maybe now the fuel is flowing more effeciently. . . . whatever.

Is there a filter actually inside the strombergs? Taking them apart may be the next move. I was hoping to get all the electrical 100% straightened out before I moved on. Now it's idling pretty well w/ only occassional misfires on #1. I know it's #1 because I put the timing light on all of the plug wires (sequentially) and #1 seems to be the only one that really misfires 'regularily'. But now 'regularily' is every 10-20 seconds (sounds like one miss) instead of just running intermittently.

Acceleration from 1-2,500 is still pretty weak and sometimes is bogging but at least she idles and if I don't put my foot into the carbs at that RPM range she seems to run ok.

And despite all my bitching I'm still having fun with it. I do wish I were driving it more than working on it but I knew she needed some sorting out when I got her. Overall she's really solid and once I get some of these bugs worked out(and she's reliable!)she's going to be even more fun.

I don't mind putzing and doing stuff I just wish I could drive her further than 10 blocks without worrying about some inexplicable problem popping up. But, I'm getting there.

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 Posted: 10-14-2005 12:06 am
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Mark Rosenbaum
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"... a really interesting spat of revving up and down between 0 and 2500-3000 rpm for a minute or two."
This sounds like water in the fuel, that was eventually sucked into the engine and consumed.  It could also be caused by serious blockage somewhere in the fuel lines -- check filters, banjo fittings on the fuel pump, fuel inlet screen (if present) on the tank pickup pipe, etc.

"... idle is up about 1-200rpms from where it was before."
Typical of Strombergs as they warm up.

"... Is there a filter actually inside the strombergs? "
Some of the fuel inlet valves for Strombergs had little built-in filter screens (see photo).  I've never cared for these myself as I think a big filter right at the fuel inlet tee not only works better overall, but is far less likely to be completely plugged by rust or sediment.  If you buy your carb overhaul kits from Delta you should get the non-screen fuel inlet valves.

"... Now it's idling pretty well w/ only occassional misfires on #1."
A perfect ignition system will still miss occasionally, say once every minute or so.  More often than that, check your points gap.  Make sure there's a proper lubricant on the points rubbing block or your gap will change very rapidly as you drive -- as much as 0.001" per 100 miles, perhaps.  Plain old dielectric grease works quite well as a lubricant here.

"... Acceleration from 1-2,500 is still pretty weak and sometimes is bogging ... "
Welcome to the wonderful world of long-duration camshafts.  With a stock engine, there's very little torque below 2000 rpm.  Much of the skill necessary when driving a car with a 907 engine involves planning far ahead to keep the engine between torque peak (4800 rpm) and power peak (6500 rpm) as much as possible.  The skilled operator will also learn to anticipate the slight delay provided by Strombergs (as opposed to the slight true bog, at low rpm's, that Del'lortos exhibit).

"... And despite all my bitching I'm still having fun with it."
Which is the point of the exercise.

"I don't mind putzing and doing stuff I just wish I could drive her further than 10 blocks without worrying about some inexplicable problem popping up."
The whole of the law for British cars is:  Drive.  Notice problem.  Curse.  Fix problem.  Repeat.

Attachment: fuel inlet valve with screen.jpg (Downloaded 261 times)

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 Posted: 10-14-2005 08:28 am
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DanHolmes
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Us Brits are all the same, cars and people alike!!

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 Posted: 10-14-2005 02:52 pm
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Mark Rosenbaum
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Dan,
Not sure I agree with your comment, as I've noticed several distinct differences between the typical British person who happens to own a Jensen, and the typical British person whose photograph happens to appear on Page 3 of one of the UK's more popular newspapers....  :^}

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 Posted: 10-16-2005 12:23 am
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Joel
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So do page 3 girls all drive Jensens?? I knew I like this car!

Ok, it still cuts out. And when it does it's sudden. IMMEDIATE drop of tach to '0'. And many times it will come back up - ie it immediately 'restarts' if you're in motion.

Actually, it hasn't died once when I wasn't in motion.

Weird. I need to look at the wiring diagram and figure out which wire on the back of the tach is the one that I need to rerun.

My it's a nice day and would be fun to drive the car. . . ;-)

Thanks for all the comments guys. I still think it's fire (as opposed to fuel) b/c it dies real sudden like - no gasp at all. And if it cuts out and then comes back on while running - the turning on is pretty quick.

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 Posted: 10-16-2005 02:32 am
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Gary Martin JH 15371
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Joel,

Yes, sounds electrical. You must have a bad connection somewhere. Try looking at the wiring harness connectors located just below the power brake booster. There are two connectors. One is for the large brown wires running from the battery and Alternator. The other connector with 4 smaller wires is for the Ignition, Temp sendor, starter wire, alternator light wire. You may have a bad connection here.

Gary

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 Posted: 10-16-2005 02:48 pm
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John Kimbrough
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Joel, you probably don't need any more advice, but, one more thought.  If you want to eliminate wiring as the source of your problem, once you start the engine, put a jumper wire between the + battery and the + coil.  It should not hurt the coil to have full voltage for a short time, but if you want to be safe, connect the jumper just upstream of the ballast resistor.  This jumper will bypass the ignition switch and most all electrical connectors, including the tach.  If the car runs fine, the problem is probably electrical through the ignition system (many connections).  If it dies again, the problem is either fuel or the little bit of the ignition system downstream of the coil (coil connector, points, ground, and maybe the ballast resistor, depending on where you connected the jumper)

Also, to turn the car off, remember you will need to raise the hood and disconnect the ignition jumper.  If the car dies, remember to do the same.

Luck,  John.

 

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 Posted: 10-16-2005 04:06 pm
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Jensen Healey
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I have had my JH stall out more than once and it was always related to the distributor cap.

Remove the cap and use a BRIGHT light to check for tracking. If you find the black fern-like patterns on the inside of the cap you have a phasing issue, (the rotor is not pointed at the tower when it fires.)

Clean the contacts with a fresh pencil eraser and check the center carbon contact with a volt meter for continuity. Clean the rotor with 600 grit emery paper.

Start the car at night in a dark location and look for leakage in the high tension circuit. This is the easiest way to check your plug wires. My car was sending the spark to the ground strap on the cap!

Replace the spark plugs again. Use NGK BP6ES or Autolite 64's. Sometimes even new plugs are bad. Do not use Bosch plugs.

Just my 2c

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 Posted: 10-19-2005 09:58 pm
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Joel
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Thanks for some good ideas. I ran a wire from the battery to the coil and drove her around for a bit - no stalling out. So now I need to goof around with the wires a bit more.

I think I saw a really good wiring diagram on here a while back - I'm going to go thru the manual too but if anyone can job my memory where this might be it would be helpful.

#1) I need to run the wire from the tach to the dist.

#2) I need to figure out what all of the wires on the dist are for. On the pos side there should be one from the tach, one from the dist - and one that is no longer necessary that gives xtra juice for starting. On the negative side there is one from the dist and one more - where is this one from?

3) I had an interesting jury rigged wire that was hot wired from the fuse box on the left hand (driver's side) side of the firewall. This wire was just basically stuck into the fuse box and runs (ran) to a relay on the right front fender. It ran to the furthest plug in towards the engine (I can post a pic later - but I'm at work right now). This 'relay' has around 1/2 dozen imputs. I admit that i haven't looked at the diagram yet - but does anyone have any idea what the hey the PO(s) was trying to hotwire?

Unfortunately, I'm out of town for another week or so and won't be able to continue the saga until sometime next week.

Cheers,

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 Posted: 10-20-2005 05:27 pm
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Lawrence Tod
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Joel

This may be of help, it is really nice and clear.

http://joc.org.uk/wiring2.htm
Just "click" on the copper coloured Healey and the wiring diagram will download.

I wanted to send it to you as a .jpeg but I see your email is private. Also the file is in excess of what is 102400 bytes so I could not attach to this reply.

Reguards
Lawrence

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 Posted: 10-22-2005 12:54 pm
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LambandAndy
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Sounds like you may have nailed this down to an electrical problem but I had similar symptoms on my Triumph Bonneville some time back.  Turned out that the vent was blocked on the gas tank.  Try running with the gas cap open slightly.

Andy

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 Posted: 10-23-2005 01:33 pm
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John Kimbrough
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Joel, I have  a whole set of simplified wiring diagrams on my web site along with a bunch of other stuff.  Help yourself.  John.

http://home.comcast.net/jrkengr2/

 

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 Posted: 10-23-2005 01:35 pm
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John Kimbrough
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Joel.  Sorry, I forgot a piece of the address.  John

http://home.comcast.net/~jrkengr2/

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 Posted: 10-26-2005 07:00 pm
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Joel
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thanks for the info guys. i'm back in town (for a couple of days anyway. . ) so i'll play around a bit and get back to you.

this is VERY much appreciated and very helpful.

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