Rover V 8 + eaton M 90 strange start up

Steven 90 · Post by **Steven 90** » Sun Jun 18, 2017 11:52 am

I have fitted a MP 90 to my lpg Land rover 3.5

On first start up it revs to max rpm with the throttle inlet on the M 90 closed , it then loses a bit of rpm and then i can see that the silicone tube just before the inlet manifold get sucks in

The engine stalls a bit and then again max rpm

Everytime the tube gets suck in and then expands.

If a measure the pressure @ the inlet manifold i found no pressure and no vacuum, when i measure the pressure on the top of de eaton where the vacuum hose are connected i get 50 KPA i hope this is minus not sure on the megajolt display.
On the tube that gets suckt in i measure about 100 KPA

My eaton is mounted on the top of the engine and runs clockwise, so this should be okay no ?

I have no idea how a silicone tube on the pressure side of a blower can get suckt in at max rpm.
The only thing i can think of is that i have no boost and no idea why.

Post by **Rossco** » Sun Jun 18, 2017 5:22 pm

What LPG system are you using?

Steven 90 · Post by **Steven 90** » Sun Jun 18, 2017 5:57 pm

omvl vaporiser modified to boost, the mixer is a simple venturie type.

The simplest system there is.
If i give more-less lpg there is no difference
If i give the mega-jolt 20 degree less advance there is no difference, the engine just wants to gooooooooooo
If it was a normaly aspirated i would say vacuum leak on the inlet

Eliot · Post by **Eliot** » Mon Jun 19, 2017 2:35 pm

some photo's would help us visualise it.

Post by **Rossco** » Mon Jun 19, 2017 2:43 pm

Initial thoughts are the boost balance to the vaporiser is not set correctly and vacuum is being applied to the vaporiser which allows fuel in without air.

If that makes sense.

Pictures would really help though

Steven 90 · Post by **Steven 90** » Mon Jun 19, 2017 3:20 pm

Rossco wrote:Initial thoughts are the boost balance to the vaporiser is not set correctly and vacuum is being applied to the vaporiser which allows fuel in without air.

If that makes sense.

Pictures would really help though

yes, i understand, with this line disconected the engine just wont start up. I revs and when it starts up i dies instant.

Pics is a problem, i am thinking about a Facebook link are somthing simple.

grts

Steven

Steven 90 · Post by **Steven 90** » Mon Jun 26, 2017 3:13 pm

Found it, faulse air being suckt in with the throttle closed.

However now wont the car start up anymore.

I tried with the megajolt ecu of and off a bitt of a backfire however it will not run anymore.

Do i need the vacuum advance to the megajolt ecu on the pressure side off the blower ?

DaveEFI · Post by **DaveEFI** » Mon Jun 26, 2017 4:09 pm

Surely it should start and idle with the MJ doing nothing - the default EDIS 10 BTDC limp home mode?

Steven 90 · Post by **Steven 90** » Mon Jun 26, 2017 5:54 pm

DaveEFI wrote:Surely it should start and idle with the MJ doing nothing - the default EDIS 10 BTDC limp home mode?

I thougt so to, have to say the battery was not full anymore, will charge it and try again tomorrow.

Checked the spark and it was not as blue as normal, so hopping the full battery will give it that more to start.

Before the blower it started perfect, even at minus 18 on lpg.

I got my megajolt program some years ago from a guy and just loaded it, now i have to tune it myself and must say i have one big question. The load on the left side from top to bottem is this going from more to less vacuum ore the other way arround ???

Steven 90 · Post by **Steven 90** » Thu Jul 20, 2017 10:13 am

It runs !

No longer the throttle in the suction instead in the discharge

New set-up blower -->dumpvalve--> throttle body----> lpg mixer
Only problem it constantly plofs ( backfires) if i giff more ore less throttle it stops.
However will not run on idle. If i disconnect the megajolt it runs worse and more backfire ( harder)

Will be playing with the megajolt now, any ideas ???

grtss

Steven