MF TEA low compression

[MikeyMonster]

Thats just gold Pycoed. ive got the head and top gasket set in front of me and a new intake valve but no springs. The tractor dealership couldnt tell me if they were different material as well.
When i said i could put the valve springs back in easy i was probably being a bit over simplistic, i did have to push really hard with both hands on either side of the spring to get the keepers to slip in, i was meaning more that it can be done with some patience and no spring compressor. I think i will go ahead and rebuild and not wait another week or two for the springs but i will have it well and truely noted that you didnt recommend skipping that step!
I will do the petrol test again.
Thanks a lot for your research, both intake and exhaust valves are magnetic which is as about as far as i can get in terms of being able to differentiate them.
Im hoping to have the head back on tomorrow but its early spring here so calvings on etc etc

 

[MikeyMonster]

Ive got the valves all back in and all are holding petrol well.
Im trying to understand the heads channels and so i went to replace a small covers gasket off the rear of the head. The gasket that came off (which can be seen on the far left of the photo) has some kind of cork insert that would i think block up this whole hole. The hole has a metal insert that can be seen in the middle of the hole in the photo. The replacement gasket (on the right of the old gasket) has a complete hole in it (or perhaps this gaskets for somewhere else.) The cover can be seen in the photo too.
Does anyone know what this hole is for and why it has the metal bar in the middle of it?
I can just permatex up the old gasket if that gasket is needed to make it function as designed



EDIT: what i think has happened is the stuff i think was cork was actually packed on gunk from the cooling system and its also bent the cover a bit from water trying to get past it, so ive straightened it. I think that this area is meant to have water passage through it hence the manufactured raised oval in the middle of the cover (this can be seen in the photo of the cover which is on the far right)

 

[MikeyMonster]

Just doing the valves which is taking quite a while as i dont have a crank handle so i have to use a screwdriver to turn her over. Im doing the 9 technique, ie when valve 8 is down i adjust valve one, when valve 5 is down i adjust valve 4. Everything has gone back together fine so i should soon be able to crank her over to get compression readings and thereafter start her again. Im picking that the exhaust valve had recessed so much in her seat that she probably wasnt sealing properly there for quite a while as ive never adjusted the valve lash before, so that recessing would never of being compensated for.

One thing im wondering before i restart is that in the breather/recirc system theres a pipe off the top of the rocker cover that goes down to the start of the inlet manifold just above the carb. Well in mine theres a thread and a screw in the hole in the inlet manifold inlet for the recirc pipe. With the screw in there there seems no way that any gas could go through there but there is a thread for the screw. Does anyone know whats going on here? Is it just to allow one of two options opened or closed? And if thats the case what option should i run her on?

 

[Agvg]

Picture?

 

[MikeyMonster]

Picture?

Yes here it is. If i remove that screw theres a hole that goes down into the inlet manifold with the screw in there its all closed up. There are threads for the screw, its not just dropped in there.
On a side note i ended up putting a bolt in the end of my car jack and have done that to turn the engine over, ive now being able to do the last half of the valves (setting their lash) in about 5mins, talk about efficiency gains. So i should have her ready for pre and post compression readings very soon.

 

[Agvg]

its probably a valve, pressure valve in the parts list, do you have the parts list?

 

[MikeyMonster]

its probably a valve, pressure valve in the parts list, do you have the parts list?

Nope, unfortunately. It literally is just a hole which takes a normal screw, so its literally blocking the hole or its removed and the holes clear..theres no moveable parts or anything else of note, just a hole.... beats me.
Oh well i will finish her off and test her tomorrow as i can still change this later if any further thoughts are said on it, cheers Agvg

 

[Agvg]

I can send you one if you want one, send me a PM

 

[MikeyMonster]

So shes back together and its now time for posting the findings. To recap compression beforehand 90,50,90,90. Cylinder two had a burnt up exhaust valve and seat which i replaced with a larger inlet valve and grinding it in with a highspeed drill, cylinder four had a worn valve too which i said I would replace but i didnt.

Compression afterwards 100,90, 100, 85
I think the engine was approximately the same temp when the before and after test was done. I think the improvements in 1 and 3 could be from the cleaning up of the valves, adjusting valve lash, using diesel to help soak and clean the rings up or also the new head gasket. The big jump in cylinder two im very pleased about. Cylinder four has interestingly dropped. I regret not putting an intake valve to replace the exhaust valve on that one too, perhaps me removing it to clean it has changed it from its bedded in seating position..
Whats left is for me to get a couple of water pump gaskets as shes leaking where i tried using the old ones and i also need to get new oil to replace that in there which has the diesel in it that im using as a flush.

The proper definitive test will be when i take her back out on the hills, so i will report back when i get her back out on her job list such as blading this track.

 

[MikeyMonster]

Well the rains eased up and i can get her out the back again. I put in new oil and after that diesel flush the oil is so clean i have struggled to even see where the level was on the dipstick.
She wasnt idling well so ive put that screw back in and shes fine now.
I took her back out and the whole way i was cowering, anticipating another big backfire in my face, none came, so she seems like shes entirely operational again. Runs very smoothly and pulls up the steep hills with no sense of hindrance.
Thank you for all those who chipped in with assistance on this