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What could be wrong with my L28
Posted: Mon Nov 15, 2004 11:33 pm
by Big Red Toy
well it use to rev cleanly to around 7500rpm but now only to about 5000rpm & then it starts playin up

i want it to rev more
The day i got the electronic ignition fitted i went for a boot up a gravel track up mt dandy & it rev out oh so nice, but it gets restictive nowa days
Posted: Tue Nov 16, 2004 7:50 am
by Fathillbilly
that sounds like the timing chain, as the chain streches the mechanical timing is retarded.
it's not a big job to fix, just make sure it's set up at TDC on no.1 when you do it
Stu
Re: What could be wrong with my L28
Posted: Tue Nov 16, 2004 11:27 am
by mkpatrol
Big Red Toy wrote:well it use to rev cleanly to around 7500rpm but now only to about 5000rpm & then it starts playin up

i want it to rev more
The day i got the electronic ignition fitted i went for a boot up a gravel track up mt dandy & it rev out oh so nice, but it gets restictive nowa days
More info please, what does it do when it is playing up?
Posted: Tue Nov 16, 2004 12:00 pm
by nischev
How old is your fuel filter could be getting blocked. Also check the filters in the bottom of the fuel pumps.
Posted: Tue Nov 16, 2004 6:22 pm
by Big Red Toy
fuel pump is new, and very fast, filters are new, it has been doing it for a while now, i have electronic dizzy and when i hit just below 5000rpm it loses power
Posted: Tue Nov 16, 2004 8:05 pm
by Screwy
The problem is that ur name is on the rego papers

Posted: Tue Nov 16, 2004 8:28 pm
by MereMale
Posted: Tue Nov 16, 2004 10:38 pm
by Big Red Toy
Posted: Tue Nov 16, 2004 10:39 pm
by Screwy
great comback einstein

Posted: Tue Nov 16, 2004 10:55 pm
by Big Red Toy
Ya ignition Problem
Posted: Tue Nov 16, 2004 11:32 pm
by harks30
hi, Ya ignition problem could be 1 plugs or leads, 2 ignition timing, 3 valve timing eg. valve clearances, 4. bad fuel. Has this happened after something you have done, like refuel from somewhere different, or changed a plug lead etc. Please let me know how ya go, where are ya from, if you are anywhere near me i could come and have a look, i live in gippsland vic
harks30@optusnet.com.au
Posted: Tue Nov 16, 2004 11:48 pm
by Big Red Toy
well its been like that for a while, its still revs high but not high enough
The timing is right, plugs & leads are good, cap etc good, i just did the clearance's and improved a little, carby has been overhauled & still same. Its not a major problem as 5000rpm is high but 7500rpm is nicer
it a bit of a pain if i'm trying to get a run up at a ledge etc, as it gets restrictive, oh well i'll just supercharge it one day
Posted: Wed Nov 17, 2004 7:37 pm
by Screwy
Big Red Toy wrote:well its been like that for a while, its still revs high but not high enough
The timing is right, plugs & leads are good, cap etc good, i just did the clearance's and improved a little, carby has been overhauled & still same. Its not a major problem as 5000rpm is high but 7500rpm is nicer
it a bit of a pain if i'm trying to get a run up at a ledge etc, as it gets restrictive, oh well i'll just supercharge it one day
mate u do know the red line in the manuel for the L28 is about 5000 rpm
if u got higher once maybe u got lucky, or ur tacho screwed itself

Posted: Thu Nov 18, 2004 7:21 am
by mkpatrol
Screwy_ScrewBall wrote:Big Red Toy wrote:well its been like that for a while, its still revs high but not high enough
The timing is right, plugs & leads are good, cap etc good, i just did the clearance's and improved a little, carby has been overhauled & still same. Its not a major problem as 5000rpm is high but 7500rpm is nicer
it a bit of a pain if i'm trying to get a run up at a ledge etc, as it gets restrictive, oh well i'll just supercharge it one day
mate u do know the red line in the manuel for the L28 is about 5000 rpm
if u got higher once maybe u got lucky, or ur tacho screwed itself

I was wondering this myself Screwy as I cannot ever remember them revving that hard because they have a reasoably long stroke for a 2.8. I wasnt going to argue it because I couldnt remember because it has been so long since I have worked on one.
Me thinks he may be pulling ones leg.
Posted: Thu Nov 18, 2004 8:09 am
by V8Patrol
the problem is ..........
its missing 2 cylinders and its not in a "V" configuration
Kingy
L28
Posted: Thu Nov 18, 2004 8:11 am
by Patroldude
Noope - my very first patrol (20 something patrols ago in a land far, far away... well 2 years ago and in the same garage) my first L28 patrol that I bought was a stocker and used to rev to 6500..... my old white L28 I had early this year or late last year (can't remember) used to scream to just past 8 but it had had a little bit of work done to it.... this was confirmed by fuel bill... driving 2 suburbs to a cafe you could watch the petrol guage go down a bit hey.....
going to build another one like it now....
Posted: Thu Nov 18, 2004 5:49 pm
by shortgq
the l28 originates in the Z cars and can produce well in excess of 300hp if set up right... the 280zx was turbocharged..... on most z car forums they confirm the l28 will rev to approx 8000 revs beyond that it develops a resonance problem
Posted: Thu Nov 18, 2004 7:53 pm
by J Top
Possibly extra crankcase ventilation
J Top
Posted: Thu Nov 18, 2004 11:04 pm
by Big Red Toy
it redlines at 6000rpm & tacho ends at 8000rpm.
It stops reving properly just short of 5000rpm and i think about 5500rpm would be handy, just that little bit more.
As for fuel consumption, well it drinks petrol fast, but it's good fun
maybe i'll just pay somebody to fix it

but that sucks having to do that
Posted: Fri Nov 19, 2004 10:10 pm
by Screwy
i wasnt sure if redline was 5500 or 6000.
But 700 is abit outa the range for a stock one.
I am aware they will rev there nuts off and will go hard, but they have to be setup right. a stock one will not go that hard.
the other thing i might add is that:
The L28 motor didnt ORIGINATE in the Z series cars ( ie 280 zx )
All the Z series cars with L28s were L28E - injected versions of the same motor.
The carb version came out first in the patrol then went to EFI in the Z series and patrol went to the TB42 in the GQ's
screwy
Posted: Sat Nov 20, 2004 3:05 am
by Big Red Toy
not all the z cars had injection, early one's had carby
Posted: Sat Nov 20, 2004 5:04 pm
by Screwy
OK.
I have some Official Information on this topic Finally.
was in at work today and did some research on this.
The L28 Motor First made an apperciance in the
NISSAN CEDRIC ( this vehicle is rare at anything and isnt even in books or computer listings ).
It was introduced in the 70s and didnt last long.
They Then brang another Carbi Version out in the
NISSAN 280 C ( NOT ZX SERIES !!!) This vehicle was the second to get the motor. It is also PRIOR TO 1980.
They then introduced the L28 into the First of the
Patrol Prototypes in 79, and introduced it officially late 79 / early 1980.
Finally about 1984 Nissan Brang out the
Nissan 280 ZX
This lasted till the late 80's/ about 5 years and it was the last of the L28 motors. This motor hoever had a difference.
It was an L28E. It was fuel injected.
So there were 2 carbi cars with it, then the patrol had it for 4 years before nissan brang out the Injected version in the 280ZX, then it was running in the 280zx along side the carbi L28 in the patrol from 84 till the end of the patrols in 87 then it was only the L28E till 89.
thats were the History is.
KINGY, IF U WOULD BE SO KIND AS TO ADD TO THE BIBLE
Screwy

Posted: Sun Nov 21, 2004 6:43 am
by J Top
How are the valve springs.Have you collapsed or broken one with the big burst you gave it?
J Top
Posted: Sun Nov 21, 2004 7:44 am
by r0ck_m0nkey
Screwy_ScrewBall wrote:Finally about 1984 Nissan Brang out the Nissan 280 ZX
This lasted till the late 80's/ about 5 years and it was the last of the L28 motors. This motor hoever had a difference.
It was an L28E. It was fuel injected.
Just a correction.
The 280ZX was released in 1979, the turbo variant arrived in 1981. The Z31 300ZX was released in 1984 and ceased with the arrival of the Z32 300ZX in 1989.
Posted: Sun Nov 21, 2004 2:04 pm
by Big Red Toy
well first i have to replace my front springs after bending them friday night
Anyhow... bit more info for people on L28's:
You will find the patrol runs the N42 heads
http://zhome.com/rnt/L28conversion/head.html#cam
http://zhome.com/rnt/L28conversion/engine.html
mmmm.... triple carbs

Posted: Mon Nov 22, 2004 7:04 pm
by Screwy
r0ck_m0nkey wrote:Screwy_ScrewBall wrote:Finally about 1984 Nissan Brang out the Nissan 280 ZX
This lasted till the late 80's/ about 5 years and it was the last of the L28 motors. This motor hoever had a difference.
It was an L28E. It was fuel injected.
Just a correction.
The 280ZX was released in 1979, the turbo variant arrived in 1981. The Z31 300ZX was released in 1984 and ceased with the arrival of the Z32 300ZX in 1989.
OK, got it slightly wrong.... But the L28 dates are fairly close

Posted: Mon Nov 22, 2004 7:18 pm
by skippy's GQ
Sounds like your valve springs could be shagged, did you replace the condenser with the new dizzy????
Lseries
Posted: Tue Nov 23, 2004 3:53 pm
by Patroldude
The L series motor has been around as you said Screwy in the Cedric (any Roy and HG fans will have heard of this car) the 240Z/260Z/280ZX along witht he 240C/260C/240k/280C and possibly (not too sure) the 2000 Super Six sedan, 2300 Super Six Sedan, 2400 Personal Six sedan and 2400 super Six sedan all ran teh 6 cyclinder variant of the L series motor....
1982 saw the first turbo 280ZX and it pushed out 180hp compared to aa fresh 150hp from a datto 260z motor with twin carbs (hitaki I think similar to the SU) found on Jags and Minis and some 4 cyc datto's....
I am looking at building a lightly worked L28 with a L26 cyclinder head and the triple webbers on it possibly (found a farmer with a set he would swap for $100 and std carb set up as its a bush beater for farm and chews too much juice he says) only thing that scares me is they are horrible to tune - I have used twins on my escorts and dattos in the past but the power is great.
Thanks for putting up the right info Screwy - I didnt wanna write even more than this! I have owned a couple of 260Z's before and I can tell you they are great - If I had the chance/choice/need for anything other than a patrol again I would go find a nice 260Z... Oh and forewarning people - these cars are umong the top 10 most influential desiggns ever built to date!! And no wonder with all the good points they have - keep an eye out at the drag strip for one coming up soon..... close to 1000 hp from a 6 cyc supra motor!!! Oh the injected L28's have super strong bottom end too.... still used in sub 9 second drag cars in Japan to this date!!!!
Imagine putting one of them in a patrol - Kingy - Afraid to say it might be a bit healthier than your 350.....
I wouldn't do it - I had constant habbit of nearly killing myself in my chev but it was funny watching 3 jap imports drifting thru an intersection followed by a 350 patrol drifting with em in the wet howling her head off.... wish I got it on video - drift guys thought I was crazy.... I half believed em too!!!!
Stock L28 usually die in the bum about 160000km if not properly maintained and respected.... how many kms has yours done???
Mk
Lseries
Posted: Tue Nov 23, 2004 3:54 pm
by Patroldude
The L series motor has been around as you said Screwy in the Cedric (any Roy and HG fans will have heard of this car) the 240Z/260Z/280ZX along witht he 240C/260C/240k/280C and possibly (not too sure) the 2000 Super Six sedan, 2300 Super Six Sedan, 2400 Personal Six sedan and 2400 super Six sedan all ran teh 6 cyclinder variant of the L series motor....
1982 saw the first turbo 280ZX and it pushed out 180hp compared to aa fresh 150hp from a datto 260z motor with twin carbs (hitaki I think similar to the SU) found on Jags and Minis and some 4 cyc datto's....
I am looking at building a lightly worked L28 with a L26 cyclinder head and the triple webbers on it possibly (found a farmer with a set he would swap for $100 and std carb set up as its a bush beater for farm and chews too much juice he says) only thing that scares me is they are horrible to tune - I have used twins on my escorts and dattos in the past but the power is great.
Thanks for putting up the right info Screwy - I didnt wanna write even more than this! I have owned a couple of 260Z's before and I can tell you they are great - If I had the chance/choice/need for anything other than a patrol again I would go find a nice 260Z... Oh and forewarning people - these cars are umong the top 10 most influential desiggns ever built to date!! And no wonder with all the good points they have - keep an eye out at the drag strip for one coming up soon..... close to 1000 hp from a 6 cyc supra motor!!! Oh the injected L28's have super strong bottom end too.... still used in sub 9 second drag cars in Japan to this date!!!!
Imagine putting one of them in a patrol - Kingy - Afraid to say it might be a bit healthier than your 350.....
I wouldn't do it - I had constant habbit of nearly killing myself in my chev but it was funny watching 3 jap imports drifting thru an intersection followed by a 350 patrol drifting with em in the wet howling her head off.... wish I got it on video - drift guys thought I was crazy.... I half believed em too!!!!
Stock L28 usually die in the bum about 160000km if not properly maintained and respected.... how many kms has yours done???
Mk
Posted: Tue Nov 23, 2004 8:57 pm
by Camshaft1
7500revs outa a L28? So having any sort of engine reliability doesnt bother you then? What kinda power would it make there anyway. stuffall. call me an ass if your L28 is ported, worked and has a big mutha cam but really is there any point revvin it that hard? i looked at dyno sheets of my last 308 and after 5200 revs, power dropped off. so i certainly didnt bother revvin it over that. surely your L28 wouldnt make more power over that amount of revs? But call me an ass if im mistaken........