rebuilder86

That's the cleanest non show spec engine bay I've seen yet. I usually go to aliexpress for this kind of thing, (prototyping and inventing). I just had a look, but yeh the problem is like u say, no cable operated ones. Only electric or vacuum actuated. Or two port cable operated :( Nope I can't find any

Is the original rolla heater control valve cable operated like that?

Mind u the official parts diagram calls the outlet the housing.

How much stuff do u have laying round there haha. Google image search thermostat housing. It's what the top bit is called. The part that bolts to the head is known as the water outlet. I learnt this when I was trying to find out what the bit we are talking about is called, when trying to find a new one, unsuccessfully. If I'd known u had oodles of em I'd have hit u up haha.

ahhh sorry i thought u meant the thermostat housing; the top bit, i didnt realise u meant the water outlet housing. yeh that 3rd one looks like it was made for your purpose lol. I recon in that first pic the housing is just backwards haha

Yeh I see what ur saying. I recon u could just drill a hole and tap it, insert a barbed thread and seal it with that white loctite gasoline resistant threadlocker, which is also good for glycol and water and alloys! Yeh electric valves seem to be incredibly expensive, that Audi used one was the best I could find. As for switching it, that's pretty easy, just stick a normally closed relay which, when energised along with the other solenoid, opens the contacts and closes solenoid number 2.

Oh and I've had three other crap cars which have headgasketted me, and yes, all three failed at the rear cylinder. All in line 4s. The only head gasket failure I've had with this particular 4k , last month, I couldnt actually find evidence of a breach and I suspect it was just the head had warped beyond the gaskets ability and it pissed coolant out into the oil, so where in the middle. Actually, number 4 is the only one which is currently showing signs of oil carbon fouling on the spark plug, so yeh, rings are probably more obviously affected by the uneven cooling.

See I think just supplying whatever can get through a 15 cm hose to the rear would be wise, then restrict that so that the temp is roughly equal across the head. Interesting that u suggest the coolant is 10 degrees hotter at the back, than it is at the thermostat. I never really thought of it like that, I thought of it like, the coolant is hotter at the back than the front, but I'm not sure why I would think that, because like u describe, it has to first make it's way past 3 2 and 1's valves and next stop is the exit to the thermostat. Actually, I've just visualised what ur saying, and yeh that's what I think is going on. There are still a few ports in the newer modified gasket which allow coolant to bypass the back of the head and shoot straight through to the front of the head. if u ask me, recon it's just generaly poor design in every vehicle. Coolant should enter the middle of the block, not the front. I think maybe what I saw with my thermometer is the result of more airflow to the front. Ur actual coolant temps will hold the answer. I'm eager to hear what u find. As for ur valve, would u perhaps be able to use a solenoid controlled valve? Like this. https://m.ebay.com.au/itm/AUDI-A6-A7-4G-3-0-TFSI-A8-SOLENOID-VALVE-COOLANT-VALVE-Magnet-Valve-4h0121671b/273013982977?hash=item3f90e6c701:g:zXwAAOSwBOtY-Joz

I recon a simple adaptor plate inserted between pump n block, cut out using CNC machine, with a relitively small outlet about 15 mm would be the absolute best approach. I have access to Cheap CNC companies here un cebu as part of another project I'm involved in, and could possible ask them to knock one up for us. With ur 2 thermometer readings, u could then tweak the hose restriction to get the perfect amount of flow through it for perfect even cooling along the entire head.

Yeh that sounds like a plan. Could u not just simplify things by teeing into the lower hose tho? I kinda feel that taking water from the heater hose is taking hot water and putting in at the rear. But teeing into the bottom hose like I suggest is also flawed because the flow would want to go out the back through the new hose then into the lower hose and back to the pump. Hmm. Need an extra seperate pump I think. unfortunately the only OUTLET on the pump is into the block itself.

Hahah wow. Internet brings out such hatred. But I certainly understand that. I think the truth is most people who sell stuff on eBay are lazy, thats why they're using eBay in the first place. Great to buy, but difficult to sell.

yeh i see. i was just listing why i thought it is worse when hot and warmed up. i always wonder how that seal up stuff, (little copper particles) manages to work so well, against that pressure coming from the combustion chamber. Ive used it in the past to get me by and it basically completely fixed my head issues haha. warped metal, no problem. fill cooling system with... METAL. just can't get my head around how it manages to fill those voids when the gases would be constantly trying to dislodge it back into the coolant. saying that, the time it saved me, coolant wasnt really being ejected, it was being sucked in and burnt. thats a good topic for discussion, in another thread, how do some HG failures go one way and some the other way.

duplicate post, sorry.

So altezza, are u saying when cold, the gas flows in the "contra direction" so to speak, backwards through the system which pushes the coolant back and up the radiator and out the pressure relief valve, but once warmed up, the gas makes its way in the std forwards direction, with the flow of coolant to the rad cap and gets ejected as gas/steam. am i hearing u right?? That makes sense, and i think i agree with that. Id allways genetally thought head gasket issues and associated performance symptoms were worse once warmed up for a few reasons. 1. More heat means more pressure in cooling system so more water gets sucked into combustion chamber on intake stroke. 2. head pushes away from the block more when hot, and any inherrent warping is made worse when hot. 3. once hot, choke or ecu leans mixture out and and moisture has more of an effect on combustion (this could be completely wrong, but its just a theory of mine) 4. once hot, the extra pressures on top of std heat in the cooling system combine to form a seriously large pressure in the cooling system, (std heat expansion, plus combustion gasses). il never forget driving my shit ford econovan back from kalbarri to perth full of about 10 fully grown men, having overheating problems all the way there, lota of stops on the way back and then bang, off pops the lower hose in the middle of nowhere haha. stranded for the night.

thats not a bad idea. i got a difference of about 10-15 degrees using the infrared laser thermometer last year (now broken) , on cylinder head between 1/2 compared to the very back just behind 4. These temps were just taken pointing it at the cylinder head near the spark plug holes. it was consisttently like that for me. can't remember exactly what those temps were, but i remember thwy were about 10-15 apart. After that finding, i have since made sure to leave the new modified head gaskets well alone with the holes blocked in the front and centre of the engine. Previously i had drilled one of them out because i didnt like it, but it was a stupid thing to do, it probably makes a signfificant difference to the water supply to the back, and further, adding a seperate hose would again improve it further. where would u get the water from, would have to be the bottom hose wouldnt it? or is there another outlet on the water pump u could use?

mm mk. i recon the cooling system is performing just as well, but as there is no way for preasure to build up its escaping. like i said, here, in gridlocked cities in the philippines, where all the public buses are just crawling through traffic, never going fast, they just don't run a thermostat or a radiator cap and it seems to go quite well for them. i don't understand it, but I'm sure theres a reason for it, beyond a radiator cap being unaffordable that is haha.

yeh i tried to find where i saw that and i can't find it. i thought it was on here. someone talked about fitting an echo motor because it somewhat lined up with the k box or something. i actually thought it was u banjo.

most people here in the philippines drive around with no cap and swear by it, but the system requires pressure to keep the boiling point up. when u say it overheats, is that according to the gauge, or according to steam pouring out of the overflow?? if ur just saying its not overheating because theres no steam, thats because its just evaporating and not building pressure. if its really behaving better in terms of heat transfer and litteraly keeping cooler with no pressure then thats just impossible and id say conditions changed between ur cap on and cap off scenarios.

i seem to recall a couple of instances where toyota echo parts have been perfect accompaniments to this engine. something about the transmisson bell housing and spline being the same (Fwd tho??), and also the engine mounts are similar. maybe because they have a computer program with a button that sais "start designing now, from generic toyota small car model" and its probably all based of a basic sizing principle.

the black female terminal in the pic is the one that plugs in to and supplys the starter solenoid when the key is in the start position. the clear/white connector on the other side should go to something connected to the key barrel (start 12v) terminal.

also i think ive gathered, that u have to remove ur dizzy to go between 10 and 20 degrees advance. perhaps ur unable to get the sweet spot in the middle. i don't know how but I'm sure its possible that this couod be part of ur issue.

when u say "running at 12" I'm sure u mean base timing right? with vac advance unplugged and blocked? if the 30 degrees u require for smooth idle is really base timing, then it sounds like either a lean idle mixture, or a compression ratio issue (missmatching parts, pistons and head to be specific). An overly lean idle actually runs better with significant advance. don't focus too much on this as ur issue, I'm just trying to make sure u have all the info. Now onto the slowing down revs dropping,. if u can't get it to run properly when u slow down with base timing at 12 degrees, but u can at 20-30 degrees, consider that this may be indicative of a lean idle condition. why? at idle, if the mixture is leaner than about 13:1 (at a guess) the combustion timing is greatly affected by spark timing, because everything is moving slower. so increasing timing can make a lean condition rough idle seemingly go away, but it will lead to detonation when driving. I'm really not sure how u are able to test this without a wideband o2 sensor but i think u have a car that is worth the investment in the test. Find a mechanic or someone with the ability to give a decent fuel mixture ratio reading. Banjo showed me a spark plug with a glass backing on it that allows u to visually check the mixture. The product is called colortune. takes all guesswork out of it. uve come along way now, remember how it was lumpy and rough idle in the beginning, and now u pretty much have one last kink to iron out.

yeh its a little wierd jungle jeep thing, however the radiator is still located well above the engine. I have the same success bleeding our bush basher ke55 (seen inverted in my avatar haha) and can also get another 500 mls in it by revving to 1200. but again, in that we have no thermostat. what is really needed is a cylinder head bleed screw. because u couldnt expect anyone to figure this out with a thermostat. the ait pocket would stay there, forever leading to 2 problems in order of significance: 1. compressible space in a compressed cooling system (defeats entire purpose of compressed cooling system) 2. hot spots at top of cylinder head where air pockets reside.

i think u may have. missunderstood my procedure. the thermostat itself gets in the way. the only way to do it with a thermostat in place would be t9 have the thetmostat hot enough that its open. that wouod mean then opening the radiator at operating temp, I'm not recommending that. the only way is to remove and then replace the tstat itself, then slowly fill the remainder. Its becoming a bit too complicated to explain on here, so i think ill have to draw a diagram. my logic is sound, i just can't verbalize it.

i seem to be copping a bit of flack for putting my findings out there. Waste of time? (so i should just leave the 500 mls that it gets out, back in the engine??) its not a waste of time, it releases about 500 mls of air from the system, this air is not the result of any impeller cavitation, its 500 mls of air. see my video again. as soon as u stop revving, the air pocket returns back into the head so u have to fill it with the revs up then let the revs go. i don't actually think that bleed hole would even help with the issue i experience. if there was any air that made it into the tstat cover it would easily rise up the top hose to the radiator. but it doesnt it sits there, forever, u till u put a wave of flow behind the air to bring it to the front. if u don't fill it while that wave is holding the air the front, and let the engine go back to idle again, the water level will settle again and gravity will push the air bubble back into the head. i see ot with my own eyes. I suspect it gets stuck in the head above the level of the water outlet and tstat area. so yes, perhaps an engineering problem. Anybody actually tried it yet or are we happy to just keep telling me I am wasting my time using my brain. and trying to help others for that matter.