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see thru gas filter

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tirebiter Jeff Garber
Dighton, MA, USA   USA
Steve,

I'm trying to figure out if you are trying to figure out why there is air in the filter or are you trying to figure out why your TR-6 has "erratic behavior".

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BigChill Avatar
BigChill Big Chill
Norwood, MA, USA   USA
If your (40 year old) fuel tank is rusty, the fuel lines can get clogged with rust, impeding the flow of fuel.

Ask me how I know.... smiling smiley



Big Chill

'75 TR6 slowly coming back from the dead...

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dicta dick Taylor
Downey, Callifornia, USA   USA
In reply to # 1601987 by tapkaJohnD
In reply to # 1601884 by dicta
Here's another opinion: Fuel gaps in the see-thru (or maybe any style) filter can be tough to eliminate completely, or for any permanence. I also use the glass type but not with the filter enclosed. (There's one before the pump and a bronze screen right before the SU intake) To get it to where there is very little air present, it is necessary to burp out the air and reconnect the line. At one time, after installing an electric pump, air bubbles appeared in large quantities, thus the see-thru filter to try eliminating them.

Dick

Thing is, (small) bubbles in the line are harmless to a carburetted car, as the float chamber 'filters' them out.
As they arrive, the level will drop by a tuny amount, the valve will open. more fule arrives and the air escapes.

They don't matter!
John

John --- I agree that small bubbles don't matter, as they escape thru carb venting. In my case however, larger bubbles were so numerous that there wasn't enough fuel so support high rpm. This being due to an incorrect installation angle of the Purolator pump. My fault, as changing it to the correct 45ยบ angle solved the problem. (When all else fails, read the instructions!)

Dick

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Fuel Controls .JPG

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modandrocker Steve N
Greensboro, NC, USA   USA
John, I've seen these pretty little filters and wasn't impressed. I would have to know more about it to pass judgement but for now....I'll stay with tried and true filters.

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modandrocker Steve N
Greensboro, NC, USA   USA
Ok.. here's the scoop..My car with it's erratic behavior all started with an electric melt-down in Aug. this past year. That's when the Volt gauge decided to make a short little path on it's own to ground without restrictions. So taking out the wood dash and opening looms with a laborious wiring repair that took months of daily attention caused so many unrelated events like suddenly the car would not go into gear. What a coincidence but I never knew I had an electric transmission. Once I put in a new PP and Koyo,new clutch master and slave cyl. welded the fork shaft welded the Eaglegate carrier sleeve then I'm ready to go...Well not really because the melt down showed it's uglyness again by what is believed to damaged the Pertronic. I went to Points and plan to stay there! forever! May have damaged my MSD so I put the older one (MSD 5) in. So...about that less than half full gas filter I've talked about brings me to my erratic behavior because of my TR. As it has gone nuts too. Honestly I have found no need to be rational about anything involving British cars or from this point on...Even rational is no longer rational! Yes today was marked a very important day because I finally got her all straighten out and Oh it ran beautifully! Of course subject to change horribly. I retuned the carburetors that had been just dandy before the meltdown.. they've turned electric too..

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
My solution was to install one of these and not worry about what was going on inside:



ZS carb repairs
kencorsaw@aol.com


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TR6 Fuel cut off #2.JPG    64.6 KB
TR6 Fuel cut off #2.JPG

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modandrocker Steve N
Greensboro, NC, USA   USA
You're right Poolboy. I had a filter like you showed many years ago. What I didn't know then would have helped me so much now. But since I know what to expect, I'll try to share with others here. " Your Clear See Through Filter Will Have Anywhere From 20% full While Running and 50% Full After Engine Shutoff. The longer the engine sits the fuller it gets (sometimes). There we go!

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tirebiter Jeff Garber
Dighton, MA, USA   USA
My solution was to make sure no air was getting sucked into the fuel line between the tank and the pump. I've seen a number of TR-6s that had a slight "vacuum" leak at the connection where the metal fuel line from the tank fitting joins the steel line that runs from the rear of the car to the front. Usually there was no evidence of fuel leaking out !!! Which was the surprising part to me, at first,

Air would enter as the fuel pump lever was forced into action by the lobe on the camshaft. It ends up, this arrangement can actually draw more fuel vacuum than it can provide fuel pressure due to the pump lever/diaphragm return spring being weaker than the camlobe/lever.

If the joint between the fuel tank line and the chassis line is not secure enough it allows air to enter the fuel supply which can cause all sorts of "erratic behavior" as well as a whole carbful of "erratc fixes".

It's easy enough to have a see-through filter that is 100% devoid of entrapped air all the time. You just need to make sure there are no vacuum leaks in the fuel line.

I'm surprised nobody else on here utilizes a vacuum gauge to check these things.

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JonK Avatar
JonK Jon Korbin
ventura, USA   USA
have had one of those in my tr3 for 30 years, no issues, at least so far!

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modandrocker Steve N
Greensboro, NC, USA   USA
In reply to # 1602384 by tirebiter My solution was to make sure no air was getting sucked into the fuel line between the tank and the pump. I've seen a number of TR-6s that had a slight "vacuum" leak at the connection where the metal fuel line from the tank fitting joins the steel line that runs from the rear of the car to the front. Usually there was no evidence of fuel leaking out !!! Which was the surprising part to me, at first,

Air would enter as the fuel pump lever was forced into action by the lobe on the camshaft. It ends up, this arrangement can actually draw more fuel vacuum than it can provide fuel pressure due to the pump lever/diaphragm return spring being weaker than the camlobe/lever.

If the joint between the fuel tank line and the chassis line is not secure enough it allows air to enter the fuel supply which can cause all sorts of "erratic behavior" as well as a whole carbful of "erratc fixes".

It's easy enough to have a see-through filter that is 100% devoid of entrapped air all the time. You just need to make sure there are no vacuum leaks in the fuel line.

I'm surprised nobody else on here utilizes a vacuum gauge to check these things.

I got home today after driving on I40 around 3000 RPMs and had slight skips in the higher RPM's. I still wonder if the car is missing it's proper amount of fuel.. The suggestion above in regards to using a vacuum gage to measure from the fuel line makes since if I take a Mini Vac the type that has a gauge, and hook it on the fuel filter's end to draw and see if the gauge shows a " Leakdown anywhere going to the fuel tank. Or just suck on the filter..Kidding!!

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NHinNC Avatar
NHinNC Larry C
Greensboro, NC, USA   USA
Glad to hear you seem to have found the light at the end of the tunnel was not a oncoming train. I had issues with skipping at higher RPMs, and had to back off the timing a hair.



1976 TR6 Mimosa Yellow - not original
Purchased July 2015

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tirebiter Jeff Garber
Dighton, MA, USA   USA
Steve N,

If you connect your mighty-Vac to the inlet side of the fuel pump I think you'd be surprised at how much vacuum is created. Hasn't any of the experts on here with a vacuum gauge ever checked this ???

Your hand would probably get very tired trying to draw enough vacuum from the tank with your Mighty-Vac pump - after plugging the evaporative hose and making sure the filler cap seal is 100% intact. You may or may not be able to equal what the fuel pump can do, however.

But yes, I believe you would see the vacuum leak-down if you got it to match the amount of vacuum the fuel pump can produce. The pump would of course be filling with gasoline as it leaks down so PLEASE be careful !!!!

If it were me, I'd stick my head under the car to see if the hose clamp is there, and in good shape and tight. Often the clamps had rusted and dropped off when I would discover the fuel line vacuum leak.

To be honest with you, I can't even remember if Triumph put a clamp on at the factory. I imagine they must have but nothing lasts forever and the cars I saw this in were older.

The high RPM miss is a common symptom of an inadequate fuel supply. Not saying that is what's wrong but checking for a clamp at the connection I mentioned is a 1 minute job. Putting a new clamp on takes somewhat longer and it's not easy to do without raising the car somehow and getting under it.

A high speed miss can also be symptomatic of a big bunch of different things that could be wrong besides inadequate fuel delivery however. That's why I was asking if you are concerned about air in the filter or about the erratic behavior/high speed miss. But you seem to be happy with how the carbs work now ...

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
In reply to # 1602594 by tirebiter Hasn't any of the experts on here with a vacuum gauge ever checked this ???


No need to be coy. You can address me, Jeff.
No, I haven't.



ZS carb repairs
kencorsaw@aol.com

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tirebiter Jeff Garber
Dighton, MA, USA   USA
Good morning Ken. lol

OK you caught me but it amazed me when I checked it the first time.

For the record I believe there are several people on here who rely on the vacuum gauge more than I do, for various reasons.

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
And just for the record Jeff I prefer 'proponent' when it comes to my association with the venerable Vacuum Gauge.
I don't think I've actually reached the 'expert' level in anything as of yet.



ZS carb repairs
kencorsaw@aol.com

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