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Wedge TR8 Running Poorly

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OK,

First diagnosis using a compression gauge provides these results.....

Left bank (from front of engine)

1 - 133
2 - 128
3 - 135
4 - 130

Right bank (from front of engine)

1 - 131
2 - 131
3 - 137
4 - 130

This was a dry test, performed twice per cylinder.

Don't see any abnormal readings in two cylinders next to each other indicating a head gasket problem, so that's good.

Might be a little low overall versus spec, but the way I've always understood how to interpret these readings, they are relatively close to each other, so also does not appear there is a "bad" cylinder or cylinders in play.

The plugs look relatively normal, a couple of cylinders a little sooty, appear to be running rich. No oil on any of the plugs.

I bought new plugs and plug wires, have a spare rotor and coil so will substitute these items one by one once the air injector plugs are replaced.

Thoughts/comments encouraged....

Chris
 
Did you ever replace the fuel filter?



Rod
 
I would also say, if it is not the filter, it is probably the carbs, might be running only on one, or the fuel pump. If I was a betting man I would say the carbs. Once the originals go bad, they are very difficult to get working well again.



Rod
 
Plugs and plug wires on... runs and idles a little better but still no improvement when driving under load. Still sounds restricted with limited power.

Fuel filter is next....probably should have looked at this already, but with the plugs out to do a compression check, putting new plugs and wires on was not a big deal. Getting the air injector rails off and finding the right size plug took a lot more time than expected. Hope to carve out a little more garage time tomorrow.

Will continue to update as more items get checked off the list. I'm still going to pull the manifold and cats to put the header on, still may be contributing to the problem.

I agree Rod, carbs probably need to go...was hoping to get a little more use out of them before investing in the carb conversion. Looks like that will be sooner rather than later.

Any links/articles anywhere on what to chuck and what to keep (what get's connected where) when doing the carb conversion? This is probably a whole 'nother thread....

Chris
 
Ok,

To ask an obvious and probably dumb question, does a carb'd TR8 have one or two inline filters. The Shop manual says there is one after the fuel pump but looking near the carbs I see what appears to be another fuel filter (looks like an original one) inline with the fuel supply with factory connectors to the right carb, with a takeoff to the left carb. The line appears to be semi-solid without simple hose-clamp connections. If this is a secondary filter, I'm assuming I can chuck the factory connector and create a hose/clamp connection to the right carb?

Assuming there are two, can both be replaced with common inline filters?

Chris
 
Latest update....

By-passed the -original- (if you can believe that) fuel filter on the back of the intake manifold. Some nasty stuff in there. Lots of clean fuel can be seen flowing through the replacement filter. Still exhibiting same symptoms however even after fuel filter replacement.

Car seems to be running on one carb only. Left carb does not move with throttle linkage, although all seems to be connected properly. I can move the piston up and down freely with little impact until almost at the top. I just barely have to lift the right carb piston for the rev's to drop off. Something obviously way off here. At this point, it has to be the linkage (although again I can see the throttle spindle on the left car rotating when the throttle cable linkage moves), or maybe the diaphragm?

Thoughts?

I think the carb conversion is in my immediate future. I'll be making somebody's house payment this month!

Chris
 
MY only recommendations is skip the holley and go with eldebrock unless you are a Holley expert. Mine came with a Holly 390 on it and I was never able to get it tuned I switched to an eldebrock and never had to work twice on it.
 
Hi Chris - before you do anything drastic I'd strongly suggest replacing the fuel filter and taking the tops off the Stromgberg until the hole where the needle goes is exposed and straying a fair amount of carb cleaner into the float assembly. Make sure you actually get liquid, not just air, from the carb cleaner into the body.

Then disconnect the line that goes to the vacuum canister back to the carb - trace the lines - and gently blow into it. You should she a nice small flow of gas like a small fountain coming from the carb body where the needle slides in to.

I had a similar problem and the worked for me. Figure 20 minutes and can of carb cleaner to give it a whirl. If it works and the idle and engine behavior confirms that you are now running on two carbs then you can tackle the linkage.
 
Thanks for the suggestion, worth a try.

I've already replaced the fuel filter near the carbs, is there one near the tank I need to tackle?

Shop time will be non-existent until later this week due to business travel. Will post again once I give this a shot.

Chris
 
Those compression numbers are in line with a stock engine. You mention that one piston lifts easily. Is that when the engine is running or stopped? If it is when the engine is not running, then the piston should not lift easily. If one carb is low on oil, then the piston will lift easily. Do you have the correct level of damper oil in both carbs? Use hydraulic jack oil for damper oil on a TR8!!! If the one piston is hard to lift while the car is running, then that carb may have a damaged diaphram. Getting these carbs to run right is very difficult. It will take a commitment of time and and an investment in the proper tools to master. Just bolt on the big carb, and headers, and put a nice cam in it. I have half a dozen stock intakes sitting in the garage now. That should tell you something about my thoughts on them. That being said, I still think an exhaust restriction is a possibility.
 

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It is easy to move the piston on the carb in question whether the car is running or not. Makes no difference. The "good" carb has some resistance and the rpm's quickly drop off when the piston is lifted slightly.

I've filled the oil on both, using a bottle of oil I've used on my MG's with success.

I'm with you, I really don't want to invest a lot of time in the carbs, but was simply hoping to drive for a few months before the heavy work (Cam, 4 barrel conversion, header) began over the winter months. Looks like I may have to move my timetable up some.

Your engine looks sweet. That's what I'm shooting for as my goal.

Chris
 
Chris,


Stop beating your brains out and do the conversion. The reason I knew it was only running on one carb, was because my 8 did the exact same thing a year ago. I spent weeks trying to get the originals working, only to finally to go to the holley conversion. I wish I had done it sooner instead of frustrating myself for WEEKS with the originals. I have not had any problems with my Holley. My suggestion is to buy the kit from Woody. Let him set it up and calibrate it for you, so all you have to do is put it on and go!

GL!

Rod
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif

YEP!
 
/bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif

Ok guys, you've convinced me. I didn't need much of a push, my only hesitation was Holley versus Edelbrock. Not looking to revisit that discussion, but seems to engender strong opinions along the lines of "less filling" and "tastes great"

/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Chris -

I have no experience with the Edelbrock, but I'm sure it's a good choice. I went with the Holley, but got it from Woody at the Wedge Shop. He set it up, based on the cam and headers I also bought from him. Money VERY well spent, as Woody had already done the numbers, and as Rod said, it truly was a "plug-n-play" deal.

Either way, you won't be disappointed.
 
Did you ever take the top off the bad carb to see if the diaphram was torn?
 
Woody is the man. Just ordered a set of coated big tube headers, aluminum radiator and fan, solid lifter cam, roller rockers, Harcourt open plenum intake and a Barry Grant carb from him to put on my friends car. He said his 300HP 4.6 liter wasn't fast enough. Lets see if this stuff helps.
 
tr8todd said:
Woody is the man. Just ordered a set of coated big tube headers, aluminum radiator and fan, solid lifter cam, roller rockers, Harcourt open plenum intake and a Barry Grant carb from him to put on my friends car. He said his 300HP 4.6 liter wasn't fast enough. Lets see if this stuff helps.
Click to expand...

Guy must have a death-wish! /bcforum/images/%%GRAEMLIN_URL%%/jester.gif

Sounds great! Let us know how it pans out.
 
Just to let everyone know, and especially to skip and others that said it was a carb problem.....it is unanimous...it was very definitely a carb problem!

95% through the installation of a edelbrock/holley conversion sourced from Woody and the difference is unbelievable! /bcforum/images/%%GRAEMLIN_URL%%/banana.gif

Looks like I need a bracket to hold the throttle cable and return spring...did not get that in the kit. I have it temporarily in-place -- enough to drive briefly. Thanks to Woody's jetting and set-up all I had to do was drop the idle down a few turns.

/bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif

Chris
 
YAAAY! /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

Now, enjoy!!! /bcforum/images/%%GRAEMLIN_URL%%/driving.gif /bcforum/images/%%GRAEMLIN_URL%%/driving.gif
 
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