Hi, here is my presentation post :

http://www.914world.com/bbs2/index.php?showtopic=337989

two weeks ago I was in Monthlery near Paris France, for a wagenfest with my 914.

Get some troubles with the engine, a hammer noise and the engine stopped smoothly like out of gas.

here is what I found :
https://drive.google.com/open?id=1gzsWwNBOh...86Kbof2P4BCHHrm

some pics

my own workshop, this is a Aircooled specialized self garage

cylinder 3 admission valve stand in open position

Opening the engine and disassembling the djetronic I found somme stranges things I will like to show you

question #1 :
the head temperature sender was not plugged, perhaps I unplugged it myself by mistake.
where does it plug ?

classic dropped valve seat.

Pull the heads and redo them.

Plugs into the ecu wiring harness.

I agree but where ?
here ?

Follow the ecu harness back from the ECU...you should see a wire with a plastic connector shield on the end of the lead. Usually the wire is white like the one I see in the picture.

Thanks, to be sure I will track the wire and the number in the ECU connector.

Another part was not plugged, the additionnal air valve.

I'd be more worried about the dropped valve seat before where the wires plug in...but that's just me...

For a guy with that shop, I don't think he worries about wires or seats.

Have the head checked for cracks before you waste time / money in machine work putting a seat back in it.

Look in the exhaust seat to the plug

After you look at the heads, consider the LN series heads from the Type 4 store, or if you have a good machinist locally consider getting new head castings from AMC in Spain and using them as cores.

It might make more sense to repair yours, but new castings are available.

--DD

Thanks friends, you are right.
I checked the head, saw no scratch, I will check again after cleaning.
Next week, I will give the head to a specialised shop
http://www.rectif2000.com/

This is why I already thinking about the engine reassembly.
Djetronic works fine but is complicated.

A pic of my selfgarage
near Paris named Atelier M8

more

If I were you I'd order a set of new castings set up by Len at HAM for replacing those. I just did mine with a set from him including having bigger valves installed (44x38). Well worth every penny!

Do you intend just to do the one head?

Buy a set of these with the coating to keep the heat out of the head.

To keep the race passport available, I need to keep the engine stock specs.

I will ask to the machining shop to check each valves, then will see.

A adress to have a quote and check if there is shipping in France ?

https://newsite.hamheads.com/home/

Contact Len Hoffman using that link.

Good money spent.

I'm considering options for heads. Checked Type 4 store and it seems they don't list the LN series. Other's looks to be for Transporters? Am I missing something?

Sorry, I meant LE series heads.

But they look to be more than just equivalent heads to the 2.0, so they may not work with your class rules.

Still, new AMC castings plus a good machine shop to replace the wear parts (guides, seats, valves, springs, etc.) which aren't great quality on the AMC heads. And I think the AMC heads come from Spain, so you can save some in shipping.

--DD

--DD

I would be rather worried about rebuilding those heads considering you use the car in competition events,with constant head cycling they get soft and don't hold the valve seats well ,the exhaust side suffers most for obvious reasons.
For what you will be spending on these old heads the AMC option is the best longterm solution,as far as your class rules go you can buy them with stock valve sizes so you should be fine.
By the way nice workshop and cars WOW.

I had a look on amc spain, 914 heads are not available yet

About head seals, on a french forum, I get the differents responses, with or without head seal between cylinders and head.
seals are on the Porsche PET.
your opinion ?

Oh no . .. . here we go.

no head seal (gasket) needed.
You can lap the cylinders to the heads to get a good seal.

Without that Head Temp Sensor, its possible that you ran too lean.
Thus, you dropped the valve.

Good luck with the new rebuilt heads, they may work out, but using old head tends to be a gamble (one I do all the time)

rich

You can get new bare 914 2.0 cores from AA performance, they come with nothing, no seats, guides hardware etc. IIRC they do come with the exhaust studs.

They would need to be sent to a machine shop, you have to use 8mm stem exhaust valves and guides.

When did people stop cheating? Sand bagging is ALWAYS an option.

This is the route I took with Len to make my set.

Bonsoir, what do you mean by lap the cylinder to the head ? (I'm French)

Use lapping compound same as used for doing inlet and exhaust valves,the sealing rings don't last and are no longer used ,have seen some cause heads to come loose and resulting leakage.
Google VW barrel to head lapping you will find more info as its hard to explain,been doing it on T1 motors for years the 914 motor needs it too.
Good luck.

tomorrow I dismount the second cylinder head and I will take them to the technician.
about cylinders and pistons, they have 30.000kms.
The segments are good but I have the impression that seen from above there is space between cylinder and piston.
Is the top of the piston a bit conical?
30.000 were made in WOT rallye position so could be used.
Which model of pistons and cylinders do you recommend ?
I do not want to machine the block but it is useful to climb a little cubic with the djetronic ?
I'm thinking about a 96mms upgrade.


Regarding the head temperature sender I found the place to plug it, thanks to 914wold community.

the actual pistons are AA 93,95

Bonsoir tout le monde, with your help, thinks are more accurates for me now.
Heats will be fully rebuild by a very good specialised workshop.
New cylinders are not expensive, will be AA perf in 96mms.
New engine and djetronic engine beam, injectors fully checked.

Question : what about a external additional oil heater ?

Since you are in Europe, just across the water talk to Rainier at Orratech Germany.

Hello, this week, heads will be shipped to the specialised shop.
Cylinders and pistons seem to be good but compare to the price, why not a new set in 96mms ?
Found 3 shops in EU, not sure all are flat pistons.

https://www.mecatechnic.com/fr-FR/kit-cylin...0-l_KD12506.htm

or

http://www.slideperformance.com/kit-cylind...bi-karmann.html

or

https://www.typ4shop.de/Motorteile-Kolben-W...-2-1L::100.html

All the wiring questions about Djectronic are done, thanks

Was surprised to found this modification on my engine

this screw is not original.
Why make this ?
Perhaps there is a link with the fact the additional air valve was not pluged, so not available.
But the problem is that the installation unable the WOT thottle position

I've seen a picture like that before...

Before my valve seat dropped I noticed my temperatures were running hotter than normal. Once I pulled the engine I noticed the thermostat had failed...and it failed closed! Yes, someone in the past used a the Mexican made type I thermostat that fails closed

Click to view attachment

Hello,
Heads, pistons and cylinders are at the machinist shop.
Now the long block is fully cleaned and I discovered severals scraches than are crossing the engine.
Some pics

more

Is the block dead ?

last one

with nail we feel an angle so the block has moved

We would call those "cracks", not "scratches".

If the cracks get into precisely machined areas, like where the cam and the crank run, the case is junk. If it is important to have that specific case with that specific serial number, a really good machinist can probably cut out the cracks and weld them up, then re-machine everything so it is in spec again.

If the cracks do not run into those areas, there's a very good chance that they will spread into those areas. Again, a very good machinist may be able to drill the ends of the cracks and stabilize everything, but that is probably not going to be a permanent solution.

The damage looks to be around the lifter holes. I would be the most concerned about the camshaft bores, because having one of those move will kill the motor pretty quickly. I wonder if that could be related to the "Type IV Syndrome", where someone over-tightens the nut holding the sump plate onto the bottom of the motor? This can bend one of the through-bolts that the oil pickup hangs from, and crack the case around it. Distressingly common.

If you have access to another case, I would suggest using it. That's the simplest way to move forward. If you do not, either find one or find a really good machinist who can weld and machine the existing case.

--DD

out side of case,,get a die kit,,,casting flaws ??

I see casting lines, not cracks.