Burnt valves - 80 series 4.5L LPG
Submitted: Tuesday, Sep 29, 2009 at 13:19
ThreadID:
72621
Views:
3940
Replies:
2
FollowUps:
4
This Thread has been Archived
Box Hill Bill
It appears the old girl has lost a fair amount of power which may be from burnt valves from running gas for the last 60K. Any recommendations on who I should get to do the head job - prefer east of
melbourne as that is where I live and work plus do you have any idea of how much
Reply By: Robnicko - Tuesday, Sep 29, 2009 at 21:44
Tuesday, Sep 29, 2009 at 21:44
Bill,
Sorry to hear that but is the power loss on both LPG & ULP?
A tell tale
sign of valves needing shimming on these is once warm and running on petrol a popping can be heard from the tailpipe at idle.
The popping wont be heard when running on LPG due to the way lpg combusts.
Also as stated earlier maybe a tune up is the go, hopefully.
Check for blocked/dirty air cleaner, replace plugs (NGK BKR6E Colder lpg plug) and leads...the most common culprits. And
check the inside of the dissy cap for arc residue on the probes.
Try AGAutogas in
Lilydale for reccomendations on the head reco.
If running flashlube I find it odd that after 60k you have this problem unless the clearances were never done prior to now.
Mine is at 310k with 200 of that with LPG and heaps of clearance left at the last
check 280k.
Good luck.
Rob
AnswerID:
385122
Follow Up By: Member - Keith C (NSW) - Wednesday, Sep 30, 2009 at 09:41
Wednesday, Sep 30, 2009 at 09:41
G/day Rob,I was interested to read your comments on flashlube.I have had my 80s on gas for about 10,000ks, the installer didn`t mention flashlube to me ,does it help engine life when using gas?Is it introduced somewhere in the air intake,I would like to know more,Is it similar to the additive they use in old leaded engines?Any tips will be appreciated. Regards Keith C
FollowupID:
652869
Follow Up By: Robnicko - Wednesday, Sep 30, 2009 at 13:08
Wednesday, Sep 30, 2009 at 13:08
Keith,
Flashlube is a lead replacement lubricant that lubes dry valves. It is sold as a kit with a bottle and metred feeder (about 12 drops per minute) that feeds via the intake manifold. You can get them from Autobarn and the 400ml bottle should last about 4000K. It is the same additive for leaded engines. I even add it directly to the fuel tank as it cleans lines, injectors and intake valve ports. It is very good stuff.
Have a look at the flashlube website for more info.
HOwever with 80's and LPG I always run
mine on petrol for the 1st 10 minutes then switch to Gas and then switch back to Petrol just prior to getting
home. I beleive this is the best way to make sure the valves stay lubricated for initial startup as thats where a sticky valve would most likely get harmed.
Rob
FollowupID:
652886
Follow Up By: Box Hill Bill- Thursday, Oct 01, 2009 at 04:06
Thursday, Oct 01, 2009 at 04:06
Compression
test came up great, 190 - 200. The upper cylinder lub obviously does its job.
Will have her tuned and the tappets checked
Thanks for your help
Bill
FollowupID:
652981