Access to spark plugs V6

[Jim the Box]

How easy is it to remove the spark plugs on the V6, does the manifold have to be removed or the gasket split, or is it just a case of an extension bar on to a spark plug socket access looks a bit tight.

[wishmaster]

I used to use a standard spark plug tool (T-Bar type), dead easy job

Izzy

[Simon Jones]

I can't recall the size of spark plug socket, but it's quite a small size and you'll need quite a long extension bar. Look out for signs of oil around the plugs which indicates the rocker cover seal may need replacing. Also check for signs of arcing and insulation damage on the HT leads.

[Jim the Box]

Thanks guys,
I'm due a service soon and was chatting to a mechanic who was on about some old Mazda engine he had to work on and to get to the plugs you had to split the manifold joint, was hoping it was not the case on the bongo engine so thats good news. Almost had my V6 a year now, only done 4600 miles since purchase but will service her annually regardless of mileage.
I am running on LPG is the plug gap any different?

Jim....

[Simon Jones]

LPG you should reduce the gap by about 0.1mm from the standard. I'm going to change mine to NGK soon and was advised to set the gap to 0.6mm which seems pretty small, but I'll give it ago & see how it goes.

[mikeWalsall]

After having to remove the floor to get to them on 'layflat' Estima engine .. changing the plugs on the V6 is the simplest job possible ..

I Use NGK BKR5E -11 sparkies .. using LPG with a tired 15 year old ignition system .. I found that closing the gap to a 'tight' 1.0mm made a dramatic difference with mine ..

A word of caution .. I noticed when I removed my plugs who ever had fitted them had really overtightened them .. to the point that the threads where distorted and 'pulled' up .. not good workshop practise particularly with Alloy heads ..!!

I use a dab off Allicote anti seize grease (similar to Copper Slip) on the threads when re fitting the new plugs ..

[Jim the Box]

That's quite a range between 0.6mm to 1.0mm (Simon's settings & Mike's) I take it the normal is about 0.7mm for std petorl engine set up. I don't want to take the plugs in and out several times as it may affect the soft washers on the plugs.
I may check the gap on the ones that come out and just reduce the gap a fraction on the new ones.

[Simon Jones]

According to the manual, the gap should be 1 - 1.1mm. Generally for LPG, you reduce it a bit, so mine are about 0.9mm. I've now just ordered some proper NGK Laserline LPG specific plugs which are preset to 0.8mm and should not be adjusted. The are designed to run at higher temps and provide a better quality spark that is needed for gas. They're not cheap (best price was just over £13 per plug), but they are generally considered to be essential to get the best performance and economy, so I think it should be a good investment.

These were the cheapest I could find as they're normally around the £20 mark:
http://www.sparkplugs2u.com/product_detail.aspx?id=2816

[Jim the Box]

Gosh Simon,I've just bought a set of NGK BKR5E-11, £12 for the set of 6 plugs, I thought NGK were the high end of the range re: spark plugs, now I find they do plugs specific to lpg at 13 quid each, you've got me thinking now.
Think I may try them (the ones I've bought) at 0.9mm and also look at what plugs I'm taking out.( 21mpg on lpg on the old plugs and nice smooth running old the year).

Jim.....

[mikeWalsall]

I use NGK Iridium sparkies in my LPG Toyota Estima .. I change them every four years it needed or not as they still come out looking brand new ..!!

I bought 6 'normal' NGK BKR5E-11 for around the same price as you ..

http://www.ebay.co.uk/itm/NGK-Spark-Plu ... 4d01718ae4

... even with changing them each year they should still be cost effective ..

[Simon Jones]

When I had the LPG serviced last week and it was hooked up to the CO2 analyser and the laptop, we could see that the combustion was down when running on gas, so that suggests the sparks are not strong as they need to be. Having recently replaced the HT leads, dizzy cap and rotor arm, I thought I shouldn't skimp on plugs otherwise I may not get the best out of my investment on the conversion.

I'll report back after I've run them for a while. Got a big trip round Scotand soon, so that will give them a good test.

[mikeWalsall]

I always clean my motors once a year for there MOT (if they need it or not) .. so today I thought I would give the Bongos engine a clean down, and at the same time show how the spark plugs are laid out (as if on a work bench) for easy removal ..

Passengers (N/S) side ..



Drivers (O/S) side .. tiny bit harder on mine as I have a side kitchen and have to prop up the drivers seat ...

[Jim the Box]

Mike
looks nice and clean, no oil around the plugs area, I hope to get my engine as clean, was planning to do it after the Mot (tomorrow) but before my planned service. Prior to the Stourport bash. Will try the plug gaps on the plugs I bought at 0.9mm, will check what plugs are in the bongo at the moment and check the gaps, obviously they may may have widened with use.
Whilst I'm down at the Stourport bash I plan to nip in to Worcester on the way home to David Connellan, who is the guy who installed my lpg system (Romano) hopefully he has time to give me a tune-up. Will speak to him about fitting the plugs Simon recommended as I am seriously thinking of fitting them if they are cost effective, they may give better mpg, improve performance, and sounds as though they will last quite a bit longer.

Thanks all for your input and advice especially Mike & Simon.

[mikeWalsall]

Unlike my Toyota Estima the V6 plugs are very simple to get to and change ..

Just be aware they are 'buried' quite deep .. you need to check the bottom of the tubes that the plugs 'drop' into .. if cam cover gaskets leaks .. oil can seep into the tubes and partially submerse the plugs ..



I spoke to three LPG fitters .. all said stick with standard plugs .. one actually said to look on eBay for some cheapo Polish made ones .. !!

Another bit of useless information and that some do not realise .. next to the Piston rings .. the greatest form of engine ambient heat exchange are the spark plugs ..

[mikeWalsall]

My sparkies have been in nearly twelve months so while messing about and out of curiosity I thought I would have a look see before getting 'this years' set ..

First thing is you need a proper 5/8"plug spanner with a rubber insert .. not only to protect the plug .. but the rubber grips the porcelain and allows you to pull the plug out of the 'tube' ..



... and a longish extension bar ..to reach the plugs down the tubes ..



As the plugs where still 'as new' I gave them a quick wire brush over with a brass bristled brush ..



.. a dab of anti seize grease ..



As I re-fitted them with the 'old' crush gaskets .. I seated them by hand .. then just 'nipped' them up with the (3/8") ratchet ..