404 / 504 Sparkplug issue

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baldrick56

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Hi All,
decided that (at last) it was time to devote some TLC to my "spare" XC engine (actually a 2.0 from a 504) that's destined to replace the current 1.7 in the 404. Removing the spark plugs I discovered No. 2 cyl was stuck tight. I squirted some penetrating oil down the hole & let it be for a while. Returning for another attempt thought I'd shifted it - but all that had happened was I'd rounded off the flats on my "official" peugeot super-deep box spanner. This dismayed me - I imagine they're thin on the ground these days? Put it on the anvil & with various hammers slowly reshaped it back to the point where a plug is a snug fit once more - don't want to use it again however till I've found someone with a forge to strengthen it - dunno - quenching perhaps??

Meanwhile Re the plug, does anyone have a surefire way of removing the coil spring plug connectors "in situ" as these prevent using a chrome-vanadium socket on the plug? If I bust one of these are they still available? (the coil springs, not the socket!) Alternatively has anyone created a CV socket deep enough to go over the spring connectors? (never seen one that large).

Worst case scenario I guess I've got to remove the head but even if this is the case would prefer to get the plug out first as I'd think its no easier to remove with access only to the "business end."

Thanks,

Rob
 
baldrick56 said:
Hi All,
decided that (at last) it was time to devote some TLC to my "spare" XC engine (actually a 2.0 from a 504) that's destined to replace the current 1.7 in the 404. Removing the spark plugs I discovered No. 2 cyl was stuck tight. I squirted some penetrating oil down the hole & let it be for a while. Returning for another attempt thought I'd shifted it - but all that had happened was I'd rounded off the flats on my "official" peugeot super-deep box spanner. This dismayed me - I imagine they're thin on the ground these days? Put it on the anvil & with various hammers slowly reshaped it back to the point where a plug is a snug fit once more - don't want to use it again however till I've found someone with a forge to strengthen it - dunno - quenching perhaps??

Meanwhile Re the plug, does anyone have a surefire way of removing the coil spring plug connectors "in situ" as these prevent using a chrome-vanadium socket on the plug? If I bust one of these are they still available? (the coil springs, not the socket!) Alternatively has anyone created a CV socket deep enough to go over the spring connectors? (never seen one that large).

Worst case scenario I guess I've got to remove the head but even if this is the case would prefer to get the plug out first as I'd think its no easier to remove with access only to the "business end."

Thanks,

Rob
Click to expand...

You need the long plug spanner that fits down the plug tube. Then it's not to necessary to remove the spring with the plugs in situ.

Many weld an extension to a shorter plug spanner.That may not work with a seized plug

Seized plugs are are common XN engines.

I'd start with a 1/2 drive hex impact socket, turn it down to fit in the plug tube, bore out the hex drive so the spring fits through and then weld to a piece of pipe
 
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I had that happen once in a 404 KF2 head. The head had cracked due to overheating, and the crack propagated up the plug threading and jammed that sucker right in there. It did come out but the head was scrap.
 
Find a piece of tubing that will drive over the nut on the top of the plug (after giving the nut a shot of your favorite penetrating oil).. Hopefully you can then unscrew the nut and remove the spring. After that you can use a good quality !/2" drive plug socket on a long extension and a big breaker bar to loosen the plug. Give the plug less than half a turn and apply more penetrating oil. Work it backwards and forwards half a turn at a time while removing. With a bit of luck this may prevent the threads from stripping.
 
I thought of that too. However I didn't relish the prospect of a "lost" nut in the plug tube. Which may prevent the socket seating.Nor the concept of starting the engine with a plug nut in the combustion area.

IMO this procedure is for the very "brave" :rolleyes:

FWIW all 404 and 504 I've owned had the tubular brass nut securing the spring.
 
Baldrick. I have a plan.
Use auto trans oil as a penetrant. If the engine is a runner,[obviously not] warm it up then put the trans oil down the 'ole. Leave over night.
Over time I have acquired a strong tubular plug spanner, I think it may have been a specialist jobbie. One of those Peugeot tools like the sump plug spanner that should have been your first buy.
 
Toyota Cressida 3litre Twin OHC 6 had best tubular spanner.
Similar setup to Peugeot.
Way better engine though redline 7500rpm still used in racing boats
May find one at wreckers in boot
 
i could be completely wrong but i would have thought the plug tubes were just pressed onto the head ,the rocker cover could be removed, tube pulled out then a ring spanner used to remove the plug ,gently. using commercials plan ,i seem to remember having to remove said tubes when i got some work done on a head ,but that was some time ago .pugs
 
^ Correct. But the tappet gear gets in the way to a certain extent.

And what Driven says is also correct...I believe a few Toyotas have the same long plug spanner. I have a couple, but they are not nearly as strong as the original Peugeot ones.

Baldrick, try using a Toyota one. If that fails, take off the tappet cover and using a pair of vise grips, twist out the spark plug tube....though you will have to replace it with sealant.

I have two original Peugeot spark plug sockets...very long. One has a half inch drive socket welded to the top....the local Pug mechanic welded it on for me years ago after I admired his.
The other one has a pissy little bar stuck through the end, but it's the genuine and original one.
Both of these have very thick walls.
You can have one of them for free, if you pay for the postage. I no longer own a 504 or 505. Just PM me and I will send you my phone number or just arrange it by PM.
 
robmac said:
I thought of that too. However I didn't relish the prospect of a "lost" nut in the plug tube. Which may prevent the socket seating.Nor the concept of starting the engine with a plug nut in the combustion area.

IMO this procedure is for the very "brave" :rolleyes:

FWIW all 404 and 504 I've owned had the tubular brass nut securing the spring.
Click to expand...

I think you'll find that most plug terminal nuts are steel. If dropped the nut can be simply retrieved with a strong magnet attached to the shaft of a screwdriver. Alternatively it could be blown out with compressed air.
 
Robmac, Mike T, Commerciale, Driven, Wildebeest, Pugwash, & Beano,

thanks very much guys - some useful pointers, and as Pugwash says, don't have to get as drastic as head removal if rocker cover & sleeve could come off. The three other plugs that came out all have the little silver coloured threaded 'pips' that come with the plug when you buy them (or used to) these are screwed down to pinch the end of the coil (which has a sort of 'hook') onto the plug so I'm imagining the stuck one will be the same (can test if its magnetic by using one of the others). A piece of pipe slightly smaller dia. than the pip knocked down onto the pip might grip enough to loosen it - I'll give that a try first & move on to other means if that fails :).
Regards,
Rob
 
Good News - the plug is released,
I fabricated a "special tool" using an old screwdriver I didn't mind butchering welded to the sleeve of a 'dynabolt.' Fed this down the inside of the coil & tapped it over the connector pip - came undone first go (though I was a bit 'off centre'). With the spring out the way used a 3/8 drive socket & got the plug moving back & forward.
IMG_1079.JPGIMG_1080.JPGIMG_1081.JPGIMG_1082.JPG

Not so good News - think I may have a problem - maybe a hole through the piston of No.2 - tried to use a remote camera down the sparkplug hole but the pics a bit inconclusive. Whats for sure however is with all plugs out engine wont go a full turn - about 1/3rd of a turn it seems to lock solid :(
PICT0017.JPG
 
Oh well....if it's a spare engine that hasn't been used for a while, they are very simple and easy to strip down. Best to do it now rather than later when its in the car. The sleeves are not difficult to take out either....use two large screwdrivers to work each one from side to side, and use the thickest aluminium sleeve base seals when re-fitting. There is a selection of them which come with the gasket kit. You don't have to measure liner protrusion, really. And do up the head bolts to 70 or 75 ft/lbs. no more and no less.
 
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