Which Spark Plugs for LPG?

[Bear Senior Member Find all posts View Profile Close Bear]

I've had a recent gas conversion and am wondering if the spark plugs should be changed now at 70k or wait till the 80k service? Also, does anyone know if the platinum plugs are suited to LPG?

Thanks

Bear

[Guest Close Guest]

Re: Which Spark Plugs for LPG?

We run a fleet of LPG vehicles and only run platinums.

[Bear Senior Member Find all posts View Profile Close Bear]

Re: Which Spark Plugs for LPG?

We run a fleet of LPG vehicles and only run platinums.

Platinums it is then, thanks TP

[GXL05 Member Find all posts View Profile Close GXL05]

Re: Which Spark Plugs for LPG?

just converted mine to liquid lpg and chenged all plugs to platinum iridium good for
100000 plus km's...

[Zapper Member Find all posts View Profile Close Zapper]

Re: Which Spark Plugs for LPG?

We run a fleet of LPG vehicles and only run platinums.

Platinums it is then, thanks TP

Hey Bear how did you go with platinums? Did you end up installing them and if so how is the rig running? If all good won't mine trying them in mine...have you the part number ? Mine is getting close to 80,000k service.

Zapper

[tkstrong Junior Member Find all posts View Profile Close tkstrong]

Re: Which Spark Plugs for LPG?

We run a fleet of LPG vehicles and only run platinums.

Platinums it is then, thanks TP

Hey Bear how did you go with platinums? Did you end up installing them and if so how is the rig running? If all good won't mine trying them in mine...have you the part number ? Mine is getting close to 80,000k service.

Zapper

Hi,

Im running a set of the "NGK- LFR6AIX-11" plugs. They have very been good to me so far. The "toyota standards" only lasted 20K after the gas went on. To be expected. Although that was still a good effort for normal plugs imho.

The NGK Iridium's should last ages though. Certainly way more pull with much "smoother everything" . I got a set off "fleabay"... Just search and you will find. A guy in Melb seems to be the best. Was both cheap and snappy on delivery for me. A mate used him as well with same results so seems to be reliable seller ..

[lc120_man Advanced Member Find all posts View Profile Close lc120_man]

Re: Which Spark Plugs for LPG?

I am running Denso Iridium Power IKH20 in mine... They are available from Toyota Dealers...

[Zapper Member Find all posts View Profile Close Zapper]

Re: Which Spark Plugs for LPG?

Thanks tkstrong and Ic120_man for the infor on the plugs .....

Would be interesting to see how many km's you get out of these plugs before they needed changing? I changed mine over at the 40,000k service and installed gas at 55,000k ,I am sitting now at 72,000km . It still feels like motor is running good with no increase in fuel consumption so it will be interesting to see how the plugs look like when I replace them.

Zapper

[Billy Junior Member Find all posts View Profile Close Billy]

Re: Which Spark Plugs for LPG?

howdy.

Was wondering the same question so I sent an email to Denso which is who Toyota recommend and this was their reply:

Dear Sir.
We suggest you to use IKH22 Iridium Power spark plug.
As LPG engine's required voltage is larger than that of gasoline, spark gap 0.8mm (IKH22)
must be used.
This engine oEM spark plug is K20HR-U11. The heat range 22 is one colder than K20HR-U11
but LPG engine has less cooling
capacity and bever gets carbon, one colder heat range is proper.

Also IKH22's center electrode is0.4mm Iridium elctrode while as K20HR-U11 is 2.5mm nickel
electrode.
As LPG engine has less ignitability than that of gasoline, spark plug elctrode must be
smaller like 0.4mm.
Our Iridium Power equips world 's smallest elctrode which can adapt any LPG engine as well
as gasoline engine.

Regarding dimension of instalation,both K20HR-U11 and IKH22 are same.
Thread diamter:14mm, Thread lebght 26.5mm Hex 16mm.

It was going to be 6week+ wait for that sparkplug so I ended up going for the Iridium Power Plus (I think it's called) because I needed to get the engine back together so the LPG installation could be finished. All is good.

Cheers

[chesty Lurker Find all posts View Profile Close chesty]

Re: Which Spark Plugs for LPG?

Hey Billy,
I been searching everywhere for the Denso IKH22 (iridium power) plugs but no one has them. I even called Denso and they have only sold two sets in the last year. Since I am on LPG I wanted to take Denso's advice and go for the colder plug with the shorter gap and unfortunately I cannot find an equivalent in the NGK range. The NGK LFR6AIX-11 is a 1.1mm gap with a heat range of 6. I could re-gap I suppose but I could not find an NGK one with a heat range of 7.

You mentioned that you had a 6 week wait on the IKH22 so you went for the Iridium Power Plus. Did you mean Denso Iridium Tough which have are VKH22 instead of the IKH22 or are you talking about another manufacturer? Also, where did you purchase them from.

Cheers,

[chesty Lurker Find all posts View Profile Close chesty]

Re: Which Spark Plugs for LPG?

I have managed to find an NGK equivalent to the Denso IKH22.
LFR7AIX is the same as an LFR6AIX-11 except 1 step colder and a 0.8mm gap rather than the 1.1mm gap. Looks like it matches the IKH22 pretty well. Hopefully I will have better luck finding these locally.

[Billy Junior Member Find all posts View Profile Close Billy]

Re: Which Spark Plugs for LPG?

Did you mean Denso Iridium Tough which have are VKH22 instead of the IKH22 or are you talking about another manufacturer? Also, where did you purchase them from.

I ended up going for the Iridium power 1KH20. I purchased these from Big Rock Toyota, Balcatta in Perth. It wasnt a straight forward order,they had to source it from the Eastern States.

I'll be using the colder plug next change (IKH22)to see if it makes much difference.

[chesty Lurker Find all posts View Profile Close chesty]

Re: Which Spark Plugs for LPG?

Thanks Billy. I managed to get the NGK LFR7AIX which are an equivalent to the Denso IKH22. They are $20 each from any Burson's outlet. I swapped them out on the weekend and am hoping I don't have to do it again for a few thousand kms. It wouldn't be so bad if I didn't have LPG but the injector rail sits right over the middle plug on the passenger side and they did not leave enough slack hose to move it out of the way easily. Anyway, all is done and it runs great. Next job is the Pacemaker headers this week

[Billy Junior Member Find all posts View Profile Close Billy]

Re: Which Spark Plugs for LPG?

I managed to get the NGK LFR7AIX which are an equivalent to the Denso IKH22. They are $20 each from any Burson's outlet. I swapped them out on the weekend and am hoping I don't have to do it again for a few thousand kms

Hey Chesty

How did those colder plugs go? Any differance.

Im going to change my plugs in the near future when I check the tappet clearances.

[mike1100 Junior Member Find all posts View Profile Close mike1100]

Re: Which Spark Plugs for LPG?

Anyone used Bosch plugs (FR7LI332S) They are a spark plug designed for gas engines. Looking at replacing mine with the new Bosch plugs, not sure what they cost yet.

http://www.bosch.com.au/content/language1/html/6578.htm

I,m running a 3.4 v6