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kenped86

Power loss problem

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My car is a 1973 tii. The last time I posted was around September and I had just broken the gear selector lever on my transmission while renewing the shifter linkage. While replacing the transmission due to the selector lever mishap I also replaced the oil pan gasket, painted the oil pan, replaced the steering box, replaced the center support bearing, and changed transmission and differential fluid. I also celebrated several holidays as the months passed by. Now that everything has been reassembled I've gotten back on the road and discovered a new problem. On initial start the car revs up correctly. After approximately 5 minutes of driving it starts to develop power loss problems. If I apply full throttle quickly the car only revs to approximately 3500rpm. I can attain ~5500rpm if I very slowly press the throttle. Initially when cold the engine easily attains 7000rpm and accelerates normally. Other symptoms include a hiss near the intake manifold when I move the throttle from idle quickly only in the power loss and 3500rpm limit condition. Cold starts require turning the engine over approximately 10 times prior to ignition. Idle is at approximately 2500rpm. My initial assumption is a large vacuum leak but I haven't been able to find anything using the propane method. During the transmission and oil pan swap I hoisted the engine approximately 4 inches and returned it. I'm hoping somebody here can tell me what I did in the past couple months to upset my car.

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badly bent throttle linkage from the firewall ?

disturbed the warmup regulator hose and connected linkage?

please remove the air cleaner so we can see

a well lit photo of the drivers side of the motor

injection pump area - linkage area -

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I'm with CD, but also wonder why you are revving a cold engine to 7K.

How much did you remove (of the intake system) when you lifted the engine to replace the oil pan?

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20130209_0816301.jpg

I didn't touch any intake manifold pieces in the process. By cold I mean prior to driving. The engine runs well at idle and after sitting in the driving idling for 10 minutes won't develop this issue. Its after a few minutes of driving that I notice the power loss. Could this also be timing related? I wasn't watching the dizzy when I lifted the engine and it gently bumped the firewall.

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20130209_0816301.jpg

I didn't touch any intake manifold pieces in the process. By cold I mean prior to driving. The engine runs well at idle and after sitting in the driving idling for 10 minutes won't develop this issue. Its after a few minutes of driving that I notice the power loss. Could this also be timing related? I wasn't watching the dizzy when I lifted the engine and it gently bumped the firewall.

How high did you lift the engine? You might have tweaked the firewall pivot point for the accelerator pedal linkage. Did you remove the distributor cap?

Here are two pics of my car

2102010016.jpg

overallgroundwireroutiing.jpg

ALSO - please replace that fuel return line on the back of the KF pump with a fuel-rated hose. You have a PCV vapor (vacuum type) hose on there now.

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Your vertical pedal linkage looks different than mine. Yours has an offset toward the top where mine is straight.

With the engine off, does the linkage bind or move in a funny way?

Did any of the sensor wires get disconnected?

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Losing power at high rpm always makes me think of a clogged fuel filter in the tank. It usually starts with loss of power above 3500rpms as the poor little pump tries to suck fuel on demand of the driver who's trying to get to 7000rpms.

:-(

Eliminate the fuel starvation theory. It's easy to inspect the filters.

The "hissing" may be the warm up regulator sucking air during coldstart.

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I put a battery charger on it last night and this morning the long starting problem went away. After letting it idle for a while in the garage I went for a drive. 40 minutes with no power loss symptoms. I'm thinking it may have been bad gas. While on jackstands in the garage for 4 months it had about 1/8 tank of gas and my first trip was to a gas station. Its probably due a new fuel filter as well as it looks most of the items on the car haven't been replaced in 20 years.

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in addition to replacing the incorrect grade gas hose,

I see hoses touching throttle linkage.

you need to straighten out your plumbing so nothing

touches during the entire movement of all

linkage rods and levers - also while holding the gas

pedal to the floor checking for FULL OPEN at the

intake throttle housing and injection pump.

A through check per the tii manual of linkage

adjustments, and cold-to-hot operation of the

injection pump warm-up regulator before you

guess about any other stuff

also do not let the car just sit in the drive running.

START, wait 15 secs. for oil circulation, THEN

DRIVE. Much better for your motor, really

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Thanks for the replies. After running great on Saturday the car had the same exact symptoms again on Sunday. I'm starting to think its more ignition related with humidity in the distributor since both Friday and Sunday were very humid days. I have no idea where that offset in my throttle linkage came from and will give it a good check. As for everyone who commented on the fuel return hose - don't worry about that. That hose has been on there for years without issue. If you had a bigger view you'd see that its actually a multipurpose fuel/eec/pcv hose from NAPA http://www.napaonline.com/Catalog/CatalogItemDetail.aspx?R=NBHH176_0395056459 that was cut just behind the "EEC" up front to give the appearance of simply being a "PCV HOSE". I'm off to tackle my engine bay cleanup one step at a time starting with new spark plugs, dizzy cap and rotor from IE :) C.D. - I've got pictures of you and Bill Williams' engine bays sitting in my garage now for help routing wires/hoses/etc. Very inspirational and thanks everyone for the help.

IMG_0839.jpg

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