pics and vids of some engine functions

[rebuilder86]

hey all.

ive talked a lot in recent posts about certain things and thought i owed it to everyone to put some pics vids of my findings up here.

everything here is on stock carburettor on a 4k-U block with dished pistons, and dry compression at about 150 PSI.

firstly, spark plug reading .

i used to have black plugs, which was a result of a rich mixture when coasting and seriously rich mixture on deceleration due to the idle circuit supplying an uncombustible overrich amount of fuel when the throttle is closed shut or nearly closed and manifold vacuum is high. This creates huge suction on the fuel from the slow jet and doesnt pull in any air at all really. The result is wasted fuel on deceleration, and poor fuel economy on coasting. to cobat this i invented a deceleration fuel cut system whereby fuel is cut by the idle solenoid (anti deiseling solenoid) when the following conditions are met.

1. manifold vacuum is above ~21 inches and

2. rpm is above 1200

this has cleaned everything up and i now have the nearly perfect plugs u can see in these pics. note that plug 3 (with my foot in background) has some oil carbon fouling, this is probably due to a poor rebuild where i had no access to reboring machine, nor a hone, so i used sandpaper to rough up the bores to seat the rings.

the equipment needed for this decel cutoff system system is a robotics vacuum switch from ebay and an RPM activated switch from jaycar.

toyota mention a similar type of system in their 2rz engine repair manual but i can find no information about the systems actual function. see attaches screenshot of repair manual diagnostics. under poor mileage they talk about this system.

next post has vids of coolant burping while revving engine.

 

edit: as it turns out its actually not my invention, but it appears manufacturers implemented its use only over 2200 rpm. this is no good for me, i get gurgling and popping in the exaust coasting/decelerating down the road at 1800 rpm in 3rd.

https://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c15280047f86

Edited November 15, 2017 by rebuilder86

[Banjo]

Hi Jeremy,

                   Nice thongs !  We should probably point out to others looking at your post pics, that the long reach plug is only suitable for the 4K-U engine, & not other 4K variations like the common 4K-C.  The long reach plug is only used where dished pistons are utilised.  

How about a few pics of your "jeep".

Cheers Banjo

[ke70dave]

yer keen on jeep pics

Those spark plugs are crazy long. I thought the image was distorted.

[rebuilder86]

here is my homemadr (jungle made) decel fuel cut system. i have achieved a saving of 30% on fuel. 

if u have a perfectly sealed exhaust system, u wont notice the problem, but the problem is still there and your paying for it. "So thank you leaky exhaust flange gasket for alerting me to the copious amounts of fuel that were being burnt after u."

u can see the rpm activates awitxh hanging from that stainless steel support, which is powered by 12 volts that i stole from the posiative on the coil, and it gets its signal (pulse) from the negative. how convenient. then its just earthed to the body and turna on and off a relay which then supplies on or off 12 volts to the solenoid.for times that the rpm is above 1300, the rpm switch disconnecta the fuel solenoid and relies on whatever the vacuum swutch has to say about the aituation.

the vacuum switch is the little thing wrapped in galv steel (a repair i made due to oil braking the plastic). it takes the 12 volts from the coil positive and lets it through to the fuel solenoid only if the vacuum is below 20 inches. less than 20 inches only occura during ANY gentle acceleration or harder acceleration.

if the rpm activates awitch wasnt there to override the vacuum switch, the engine would pull vacuum all the way past idle on slowing down and stall out. the rpm switch forces the aolenoid open under 1300 rpm so its impossible to stall.

[rebuilder86]

YES thongs, if i use that word here they laugh because it means g string.

yeh nah the jeep is looking pretty ragged these days. all maintenance goes into the engine and driveline and i do nothing on the body. its rusting apart unfortunately. Its nothing special, but it does now run on the smell of an oily rag. 

[rebuilder86]

so here ive put on youtube a highly compressed video of me revving the engine showing the coolant level changing in the top tank.

in order for u to do this with a thermostat, u have to be brave and heat up the engine to open the thermostat then open the cap and follow my procedure. i suspect many people will die if they do this, so i take no responaibility to foolish cap opening incidents. use a rag over the cap and make sure the overflow hose is secured, prefferably into the overflow tank.

my overflow tank is a water bottle with a hole in it... see.

without this coolant has a one way trip out ur radiator back to nature. and ur tank must have liquid in it or else the steam just leaves as .....well,   steam, toxic steam.

youtube links.

 

[Banjo]

That's insane !    I've never heard anything like that in all my Rollas over many years.  My Jacuzzi with a party going on, doesn't even make that much noise.

There is something seriously wrong inside that engine.  Can't believe all that noise, is caused by a a 0.5 liter of air trapped somewhere inside the block.  That's serious cavitation, like when a outboard motor propellor is lifted part way out of the water.

Cheers Banjo

[rebuilder86]

now for the widely missunderstood pcv valve.

I don't think ive seen a video like this on youtube and its about time someone did one.

The important part from my video's description is the point at the end that the most blowby for a carburetted engine happens during coasting and decelerating.

In these conditions, the valve is closed and isnt pulling out the excess blowby, giving the bad gasoline rich vapours more chance to settle into the oil and dilute it. 

During power scenarios, the rings are forced into their seats and seal propperly and the issue then comes during the transfer to the exhaust stroke where water vapour as a byproduct of combustion, gets forced past the rings while they are changing from bottom seat to top seat. This is where a crank vent, which is positively sucking is absolutely required. 

My oil is cheap junk. i cannot get nice oil like in australia with good anti foaming agents. so after a good hard drive, my oil filler cap looks like this (see attachment)

Someone might get worried when they see this and blame the head gasket. the issue here is actually that the pcv system isnt strong enough to suck out all water vapour and the anti foaming agents are required for this reason. In these older engines, we need this particular additive because of the loose tollerances of the ring seats. a foaming agent helps the oil stay smooth so that the water is forced to evaporate. if it foams, the water gets stuck to the sticky parts in the rocker cover. 

Note that my oil is 100 percent water free when visually inspected after a full drain. I check it everytime out of fear of a warped head or failing head gasket. This shows the water is more of a problem in its vapouros state. 

 

My plans for this engine is to prototype a diesel vacuum pump and alternator assembly rom a diesel engine, mounted to my petrol engine without a PCV valve. I plan on taking the freah air supply hose and running it from a filtered inertial seperator like that used in a turbine engine seaplane, and avoid connecting it to the intake piping. (deceleration forces dirty vapours back the freah air line and all over ur throttle body and into ur fuel bowl vents down into ir float bowl.)

i have found the perfect handheld vacuum cleaner for this  part and am waiting for a cheap one to show up on ebay. The idea is to remove all moisture from air entering the crankcase so foaming is not an issue. I live ina. very humid environment.

The vacuum pump running from the alternator will make the pcv system operate purely on RPM without relying on vacuum.

this is a project for next year.

https://youtu.be/2ECFT3yYhZw

[rebuilder86]

4 minutes ago, Banjo said:

That's insane !    I've never heard anything like that in all my Rollas over many years.  My Jacuzzi with a party going on, doesn't even make that much noise.

There is something seriously wrong inside that engine.  Can't believe all that noise, is caused by a a 0.5 liter of air trapped somewhere inside the block.  That's serious cavitation, like when a outboard motor propellor is lifted part way out of the water.

Cheers Banjo

haha nah its really not that loud, the microphone on thia phone pics up certain sounds and they overtake everything. ignore the audio haha. i just listened to it and yes i would see why u would say that. the engine is purring and quitet. it sounds terrible in the vid.

maybe this oppo has a speech microphone only.

maybe i should try another video of the good idle i have managed to get going for others to benchmark against... hang about.

see i have too much spare time here. i don't work for 6 mths and get incredibly bored. the result is an obbsesive compulsive love for engineering haha.

[rebuilder86]

I think its this video compressor. (sunny burger video compressor) i can't upload straight videoa because I'm in the jungle on a 3g data connection where i pay for every GB and have an upload speed of about 0.1Mbps

i just recorded some of the jeep but it still sounds terrible. the trebble is amplified and all other frequencies seem to be muted. here it is anywway.

ignore the sound, its completely wrong. I'm not really much of a youtuber so microphone sound quality hasnt been my biggest purchasing decision when buying this phone.

 

[rebuilder86]

hmm that audio is just so appaling.  i jist tried an uncompressed attempt at 1080 p and it sounds like u are underwater when i play it back. damnit.

really don't wanna pull the iphone  out but thats what I'm doing now.

[SloRolla]

wow, those are some creative ideas. Goes to show how strong these K motors are, even in the toughest situations they're still kicking! Onya Jeremy. Plus that jeep sounds like a duck flapping in water ;)

[rebuilder86]

here we go, iphone 4s is superior with sound quality.

https://youtu.be/Mws2aA4gHnQ

[rebuilder86]

yeh exactly slorolla, these motors are awesome. if i was on the mission to mars, i wouldnt let the rocket take off without a good supply of these motors.

[Banjo]

 

Hi Jeremy,

                   Just checked out your video of the Jeep.   I can see your problem right away.   You forgot to put your suitcase in the second boot / trunk there in front of the radiator.

What the Hell !   Do they put straight 6 cylinder engines in these "jeeps" also ?

Cheers Banjo