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loose power in 5th gear help?!? common


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I tried everything.... Adjust the fuel timing and everything. But whenever I go on the hwy the 4th and 5th gear makes the engine slowly die. I went home adjusted the carb since it was fouling my plug's... Fix that, engine worked better and went on the hwy again. No good Still the same thing. Checked the timing and advanced it as much as I could... Was nice and revy! VERY NICE and quick!! But once again on the HWY 4th and fifth gear was no good. I went home and parked it... Tried to pull it out and reverse would not go in... The only way that it can go to reverse was when the car was off. Then I tried to go forward and the same thing occurred. Now I"m guessing the clutch is burned or I installed the wrong throw out bearing... I read the forums and it seems that I could of installed the wrong throw out bearing. What is your guys opinions? Or I guess I have to learn everything the hard way. Any advice is greatly appreciated.


This is what I have.... L20b, 240z aluminum flywheel, Throwout bearing I believe was from the l18 tranny. Clutch is unknown...


Here are some pics




Could this be causing it?

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The next time it baffs, immediately shut off motor and pull over. Check the bull's eye sight glass on the front of the carb. If there is no gas showing check, hell replace, the inline fuel filter and check the screen at the fuel inlet to carb.


If the clutch was working and suddenly it isn't then the throwout coller is probably the right one. Sounds like the hydraulic system has air in it or low fluid, or a leak. If you just put a new clutch in it the extra pressure probably blew out the tired out slave cylinder.


Check the clutch master cylinder for fluid.

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Ahhh! That's some good ideas... I never thought of a fuel starvation problem... But its a Weber... No bowl man... I guess I have to replace the clutch since the arm is hitting the tranny... Not good! Plus I remember that the original clutch cylinder pin would not disengage the clutch so I made a bigger pin. So I'm going to replace that bearing adjust the valves and see what happens.... And also block the fuel return system...

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Could it be that the T/O bearing or sleeve is wrong thus causing the loss of power on a hill or just not enough grip in the higher gears that cause the clutch to slip????????

If you say the clutch arm is fully FWD towardx the motor block then I assume it could go more FWD as the clutch fingers would still be pushng on it and bell housing opening is not letting it go fully FWD meaning the clutch disc is not fully mated. So when in higher gear when torq is applied its starts slipping.


Is there a Bur not letting the T/O bearing/sleeve go fully rearward??????


So is it loosing power but still reving up? Then that a clutch slip.


Or if its loss of fuel I would think this would still happen in the lower gears 1 2 3 as the rpms are up it would cut out.


another loss of power on the Top End is the cam is adv too much. But I assume you know How to time a cam/chain/dizzy set up as per previos posts.


UYour having bad luck with the rig. I think you should take your time and read up more. YOu have to be spec on waht part u use when it comes to clutches as they are different . I had a wrong T/O bearing and sleeve assembly from the Parts store box installed. all I had to do was compare from the orginal. I was too in a rush(had to drop the trans again) It was a Z car T/O bearing and sleeve. and we know those can be very differnt


YOu say you have a 240Z alum flyweel?????? so this would be a 225mm disc and L18s have, as I know use a type T/O bearing/sleeve like in a 510/521 L16/18 200mm set up





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May be a long shot but you mentioned you had a hard time shifting [reverse]. The clutch fork on my 620 came off 3 times & before it did i had a hard time shifting & it felt like it was slipping. Turns out the ring clip that holds the T/O collar on was installed backwards. I put it back on the correct way [sorry didnt take pics of it] & re-bent it to give it more tension,re-bled the clutch & now it's awesome!

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I just got a timing gun and well it was way way off. I know that the chain is on correctly, "pointer pointed at zero and the V inside the dash but the dash is a little to the right" But now I have to calibrate the distributor. Either it was too retarded and or to advanced... IF SOME ONE IN MY AREa CAN LEND ME A HAND PLEASE DO SO... I'LL PAY FOR SOME TOO LEND ME THERE HELP AND DATSUN WISDOM.... SCHOOL STARTS SOON FOR ME AND WELL I'M RUNNING OUT OF TIME... LET'S SEE WHAT I CAN ACCOMPLISH TOMORROW... Thanks FOR ALL THE ADVICE!!!!

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