Rough idle on petrol/lpg

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RichieH
I'm new, be nice!
Posts: 7
Joined: December 13th, 2014, 10:18 am

Rough idle on petrol/lpg

Unread post by RichieH » January 15th, 2015, 9:58 pm

I've recently picked up a hilux with petrol and lpg. The engine has a rough idle but because everything else came up great on the mechanic's inspection and the price was below market value, I went with it.
I've got a feeling that the exhaust side valves have been damaged with lpg use over the years and was wondering if anyone has had a similar issue and what it cost to put it right?
Thanks!

typhoeus
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Posts: 2058
Joined: February 6th, 2011, 8:25 pm

Re: Rough idle on petrol/lpg

Unread post by typhoeus » January 15th, 2015, 10:31 pm

I have a 3rzfe on petrol/lpg. you will find that lpg will contribute to valve seat recession. If you are lucky, a valve adjustment will fix it. set the exhaust valve gaps on the loose side. Use iridium plugs one range cooler than standard. Did you give it a compression test? are they all within 20 PSI of each other or less?. If you need shims there is a place I get them from in Melbourne, for around $8 each delivered to Sydney in any size you need. There is a process. after you have carefully measured the gaps, you pull the shims out and measure them. you may be able to swap thinner shims around to mix and match, then you only have to replace the thickest shims

RichieH
I'm new, be nice!
Posts: 7
Joined: December 13th, 2014, 10:18 am

Re: Rough idle on petrol/lpg

Unread post by RichieH » January 17th, 2015, 4:02 pm

That's great inf thanks. Wasn't sure what the steps were.

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