Rear Spark Plugs 912

[Porscheblue]

Anyone got any tips/tools for replacing the spark plugs,
particularly the 2 rear ones. Can’t do better than 90mins for the left rear one!!
Did Porsche want nobody to do this themselves?
Thanks.

[AndrewSlater]

When I first started changing spark plugs on my 912 I had the same problem.

The first thing is to preferably have the correct tool. It is essential that the spark plug tool has an effective rubber insert to tightly grip the plug correctly.
If not you can waste hours trying to fish plugs out of the tinware.

It is also worth having a mental note of the orientation of the spark plug tool when you take the plugs out, as it will help relocate the blind holes.

With the original tool, insert t bar, slacken plug ( rear left has at least 1mm off spare room so keep your swear box handy ), remove t-bar and hand wind the plug out.
Again ensure the new plug is gripped securely in the tool, remember the correct orientation and hand tighten in ( without the t-bar ). Once you have the plug hand tight fit the t-bar to the tool and torque up.

Once you have a technique they are pretty quick.

Hope that helps.

Andrew

[Mike Smith]

Andrew`s advice is very good but you might also want to buy a Telescopic Socket Wrench from PRS

www.prs356.com - you will find it under Parts and then Tools

You will still need a 3/8" Drive Ratchet Wrench to be able to use it

[Porscheblue]

Brilliant. Thank you both.

[neilbardsley]

I use the PRS tool and its great. I can get a plug in/out in under a min. However, it took 10 mins to get the lead on plug 4!!!

Sent from my Mi A2 Lite using Tapatalk

[wildtexas]

The spark plug leads with the short connectors are a real pain on no. 4, hence why I use the long type. Got them from rpl.

[Robind]

Agree the PRS tool is great but getting the plug lead on the rear takes the time

[neilbardsley]

The spark plug leads with the short connectors are a real pain on no. 4, hence why I use the long type. Got them from rpl.

It wasn't the length of the connector. It was more the cap type on the connector. One connector expects you have removed the terminals from the plugs. While the ones I have now, and are a pain, expect terminals to be on so there is less error room when getting the cap to fit.

[wildtexas]

Neil, I assume you have the Beru leads with the shorter black connector cap? They require the little caps to be threaded onto the spark plugs? A real pita to get it onto number 3?

That's why I went with the longer brown cap version from rpl, I think they come from Stoddards in the USA.

No adaptor required, just the thread and really easy to get a grip and push the leads on.

Matt

[KS]

912s, Pah! You want to try changing the plugs on a VW engine fitted with 48IDA Webers. Now that's fun...

[neilbardsley]

Neil, I assume you have the Beru leads with the shorter black connector cap? They require the little caps to be threaded onto the spark plugs? A real pita to get it onto number 3?

That's why I went with the longer brown cap version from rpl, I think they come from Stoddards in the USA.

No adaptor required, just the thread and really easy to get a grip and push the leads on.

Matt

I had those on it but some of the leads/caps were getting old so I replaced with a set bought from someone on here.

[Dingbat]

Hi , first off its the front spark plugs and I used to deal with them by putting the car up on stands, which it would be for servicing anyway , removing the rear wheels and then with the motor supported on a trolley jack I would undo the rear motor mounts and lower the motor until I could see the plugs from inside the rear inner wing, you can tilt the engine and gearbox quite a reasonable amount without doing any harm although you might want to disconnect the wiring to stop it being pulled , this may sound like a palaver but it's a lot less hassle than sorting a crossed or stripped pug.

[Timo]

Wow! That sounds like a lot of work.

I’ve always just done it by putting the plug into a proper plug socket (usually with a rubber insert which stops the plug falling out when inverted) then holding the socket c/w plug in your hand reach round the carb and screw it in by hand until it goes tight, then nip each one up using the correct bar and extension, sometimes the u/j fitting is needed also. Usually takes a few minutes for each plug.

[Mike Smith]

Just as an aside to the above

If the plugs are tight to remove - it is a fair bet that the Heads are cracked
Usually between the Inlet Valve Seat and the Spark plug Hole and usually the 30 degree Late Heads
It is carbon in this crack that is making the Plug difficult to remove

[Timo]

Great bit of info Mike