80 tr7 losing power

[john lewis]

broke down yesterday had to get towed home seeing where alot of u if u seemed to think it is gas i took gas filter off again there was no gas in line or filter so im going to put on new gas filter and new line and run it to a jerry can to see if it will run i will try to fill up line before i put it intank but if there is something else i should do please tell me thanking u in advance for whatever help u can give me john

[Hasbeen]

John, pull the top off the fuel pump. It should be 6 [I think}
screws, in the top, & you can do it in place, if you wish. Some pumps, [replacement ones I think] have one nut in the top to remove the strainer cover.

There is a strainer in the top of the pump, that could be blocked,
but more likely is that the pump diaphragn could be split, or have a
hole in it.

Have something like a pencil to push into the hose from the tank,
when you remove it from the pump. Fuel gravity feeds, [syphons] from
the tank, & runs out the hose, when it's disconnected.

If it doesn't try blowing back through the pipe to the tank, to
remove any blockage in the line.

Hasbeen

[saabfast]

On the assumption that there was fuel in the tank (gauges can be duff, mine showed full all the time when I got it), the tank may be full of crud causing the line to block. Although its best to take it out and flush it it is a lot of work. If there is still fuel in it suck it out with as much of the muck as possible, either through the top with a pump or through the float hole (remove the float). I used isoproapnol mixed in to assist in absorbing water which lays in the bottom under the fuel (and causes the rust). There is a filter on the float unit which might need cleaning.

Alan
Saab 9000 Stg 1
Saab 9000 2.3 FPT Auto
'81 TR7 DHC

[john lewis]

drained gas tank, put new filter, fresh gas in tank,which is new flushed out gas line everthing was good drove about 3 miles stopped 2 twice for 3 mins each went out started and drove home and it died a couple of times going home there is a ground (earth) strap hanging down behind motor noticed yesterday while working on tank ill check today wondering about valve pan gasket when i shut car off i see oil coming out the top under pan i ordered a new gasket could that be my problem if so can i use a good gasket making silicone good thing i got clock gas gauge and low gas light working john

[PeterTR7V8]

John, is this a V8? Does it have an electric fuel pump? What carb is it?

You said earlier that the carbs were checked & were ok. Was the fuel pressure checked?

Does it cut out when idling or does the car have to be driving? Does it cut suddenly or get rough before dying?


Never say die. At least not while you're still breathing.

[john lewis]

no not 8 4cyl., no not electric fuel pump, zenith carbs when it is working it works perfect then u feel no response to gas pedel then it stalls u downshift seems to come out of it takes gas and works great again yes it does stall out sometimes when idling if u start and stop a few times carbs were checked but i dont know if presure was checked it works perfect 95% of time, but im afraid to go any distance now i go 10 miles then head back when u shut motor off it spits a good amount of oil out of valve cover gasket would that have in any way be resposible for my problem looking at my electronic ign allison crane it has a cicrle in middle about size of quater it is held in place by a screw on both sides it looks a little rusty on the flat side should i take it off and clean it do u think, im thinking it is some kind of resistor till tomorrow ill keep thinking thanks again john

[FI Spyder]

Does the oil leak from gasket (bottom of valve cover) or top of the valve cover (in which case it is broken or missing o rings on the valve cover screws. Reguardless I'd doubt it has anything to do with your problem. My guess is ignition, like an intermittently failing electronic module that may be thermally triggered or broken wire that intermittently makes and breaks and may not be obvious if the break is hidden within the insulation.

While rust in distributor may not be the problem by all means disassemble it and clean it up keeping a sharp eye on anything untoward that may be the cause.

I have my doubts about fuel pressure but don't rule it out as making assumptions is the first step down the garden path that is not the yellow brick road. (talk about mixing metaphors.[:)])

TR7 Spider - 1978 Spifire - 1976 Spitfire - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra

[Hasbeen]

John, if it comes good from a down shift, it's unlikely to be a fuel
shortage.

More likely a poor electrical contact, or even a broken wire, held
in place by insulation, or even the harness, making contact, most of
the time, but occasionally loosing contact.

That or something trying to fail as it gets to working tenp, but not
quite done yet.

Good luck.

Hasbeen

[PeterTR7V8]

You don't think it is flooding?


Never say die. At least not while you're still breathing.

[Hasbeen]

No Peter, it would have to be really bad flooding.

Once you are driving along, at anything around or above 2,000 RPM,
the thing will be using fuel at a similar or greater rate, than the
average flooding rate. In other words, all the "flooding" is doing
is supplying some the fuel you require.

If flooding is that bad, it will still only show up, when you stop,
& idle. This is about the only time the flow from flooding will
exceed the fuel required for the engine. That is, unless the needle,
or float are jammed pretty wide open, under which circumstances, it
would not run OK most of the time, & you'd see the fuel running out
of the carbs.

I have never known of flooding cutting the engine dead, they usually
run very roughly for some time, before they stop. I have known for
blockages to do it, but that would not respond to a down shift.

That's sticking my kneck out, isn't it.

Hasbeen

[john lewis]

i concur think it is in ignition going to take the silver thing off my electronic ign. and clean it double check all my conections and hope,going for a run later today i sort of think that as long as im giving it gas it doesnt happen it is when im coasting without giving it gas is when it happens bringing it back to gas not sure about this spent last night thinking about it,hope to check today

[PeterTR7V8]

Once my Holley went haywire & flooded the chambers so bad the motor stopped turning because it wasn't able to compress the fuel. I had to wait 5-10 minutes for the fuel to drain away (yikes!) before I could get it started. So it does happen & it is worth ruling out especially with a head-scratcher like this. I don't suppose the dipstick smells like petrol?


Never say die. At least not while you're still breathing.

[john lewis]

when it stalls out by downshifting it will restart unlike your problem where u had to wait for them 10 mins. to drain this starts right up again seems like i downshift bring revs up and it goes great again, the silver thing i wanted to clean i couldnt get 1 of the screws off started to strip but i cleaned with wd40 and a wire brush worked great perfect in fact for 17 mile went on highway for 1st time in 5th had tack saying 3000 gave it gas did not respond upon downshifting brought revs up perfect till i got home i did keep revs up to around 3000 i go fri for gov. safety inspection hoping it doesnt cost much to get it thru, do hear a clunk in rear tire when i shift till tomorrow when i go back on wire patrol i did check oil no smell or water as i said before it will spit some out of valve cover gasket when i shut car off when i check oil it was always to high it is still to high by them having to much oil in it could that be the reason it blew gasket this car starts better then anything i ever owned and it works GREAT just dies but always comes back thank god till tomorrow

[john lewis]

had wife with me today when i gave car gas and it didnt respond she (wife) stared to choke up from the smell of gas the car died a couple more times and she could smell gas so my apolgize to peter it may be flooding but it keeps going so i dont know point me in the right direction y would it flood when it is working good then all of a sudden dies no response from gas i keep pumping and she starts to rev up again and u can smell gas goes great for a while seems to work best if im running 3000 rpms think ill attack from another area for a while lookingb for ideas thanks john

[PeterTR7V8]

Well I've never been right before so I understand. [8D]

If a carby float has a leak & is slowly filling up with fuel it will gradually get worse. It may also be a stuck valve at the top of the float chamber but a new filter ought to have prevented that.

But before you get your hopes up it may be a red herring. It is just a good idea to check that the whole system (carbs & ignition) is sorted when dealing with misfires. On old cars if it hasn't been checked recently it will probably be in need of a good tinkering.


Never say die. At least not while you're still breathing.