924Board.org

924LUX · Joined: 03 Aug 2006 Posts: 52 Location: south wales

Right then

i had just finished fitting my shinny new crank shaft and bearings to me engine (that was still in place), when i turned her over for the first time in about..... forever, it started lovely with no loud nocking to be heard at all

when i noticed after doing the little dance of joy that the rev counter was not holding a stedy reading,

and jumping up to 456 thou evan thought the engine was running smoth as. any body had this prob b4 and know how to fix

. i submitted a poll a few months bck about oil pressure and crank shaft condition, and if there dirrectly related and low an behold they are my readings are 6-7 cold and 3-4 bar warm so thanks those who answered you saved me from getting a pump to

i did make a few video recordings of it being started during the final stages but i dont know how to post them

sorry.
_________________
1985 Porsche 924LUX 2 ltr N/A

every cloud has a silver lining except the mushroom shaped ones in which case thats a bad thing !!!

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

Check the FAQ. . .jumpy tach needle answer lies within.
_________________
Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

924LUX · Joined: 03 Aug 2006 Posts: 52 Location: south wales

this is all i can find there :

"My speedometer/odometer is bouncing/not working. Why?
The speedo is mechanically driven off of the front left wheel"

Im on about the rev counter any sugestions?
_________________
1985 Porsche 924LUX 2 ltr N/A

every cloud has a silver lining except the mushroom shaped ones in which case thats a bad thing !!!

Ozzie · Posted: Sat May 19, 2007 9:55 am Post subject:

The tach is electrically driven of the coil- bad wiring is usually the cause.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

924LUX · Joined: 03 Aug 2006 Posts: 52 Location: south wales

have checked the connections on the coil and have filed and copper greased the earth points by the fuse box and still its bouncing

what kinder test could i do on a multi meter apart from a continuity test to see if its the wires themselfs that are at fault and is there any other places that the cables go to endup at the display. as far as i can gues its from coil to fuse box then display, is this any where near correct ?

_________________
1985 Porsche 924LUX 2 ltr N/A

every cloud has a silver lining except the mushroom shaped ones in which case thats a bad thing !!!

Jaf · Joined: 08 Jun 2006 Posts: 194 Location: Oria. Spain

Sorry I'm no help about the rev counter. Just wondering where you got your crank from. I'm about to take a look at mine to see whether I can get it reground or not. Also how'd you go about getting the main crank to pulley bolt off? I tried years ago but bent my mates snap-on breaker bar! He was not impressed.
_________________
1978 924na

Ozzie · Posted: Fri May 25, 2007 8:58 am Post subject:

Jaf · Joined: 08 Jun 2006 Posts: 194 Location: Oria. Spain

924LUX · Joined: 03 Aug 2006 Posts: 52 Location: south wales

to get the crank pully off i had the engine out once b4 and losend it off then since the car had not been on the rd since it was easy enough to get off lol i got the crank from a guy in newport sold it to me for £130 plus all bearings to mach the reground it had dont know if he has any more though. going back to rev counter does any one know of a decent wiring diagram of this circuit thanks.

_________________
1985 Porsche 924LUX 2 ltr N/A

every cloud has a silver lining except the mushroom shaped ones in which case thats a bad thing !!!

Ozzie · Posted: Sun May 27, 2007 4:01 pm Post subject:

The late model 924 had the same tacho as the 944 without the economy guage.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Paul · Posted: Mon May 28, 2007 5:42 am Post subject:

A 944 tach gets its signal from the DME.
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Ozzie · Posted: Mon May 28, 2007 7:59 am Post subject:

My tach has two multiplugs, one going to the speedo and the other going of to the coil etc.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

924LUX · Joined: 03 Aug 2006 Posts: 52 Location: south wales

DME???
_________________
1985 Porsche 924LUX 2 ltr N/A

every cloud has a silver lining except the mushroom shaped ones in which case thats a bad thing !!!

Paul · Posted: Mon May 28, 2007 11:00 am Post subject:

I don't know if a 2 liter 924 ever had one....

Bosch Digital Motronic Engine-management (DME)

http://www.atlllc.com/atlantis.php?page=Motronic%20Editor
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Ozzie · Posted: Mon May 28, 2007 2:27 pm Post subject: