08-12-2019, 09:39 AM
(08-08-2019, 02:31 AM)fixkick Wrote: the surge, J18.... (some grown men cry, and for good reasons)
yes, its a really silly thing this, reverse flow. stat system.
lets say engine fully hot,
the 22 tube is plugged. or 1/2 way. or heater core missing and bypass hose too.?
the 22 very hot water, does not land on the wax puck now. (very bad this)
the thermostat will falsely close due to water temps too low at wax puck.
then the pump and engine start to roast, super hot and that hot water backs up to the WAX (via pump housing from HEAD jackets)
the wax feels (if you will) the super hot back flow of hot water and slams full open.
then that very cooler now super cool water for sure moving fast, the cold water hits the WAX and slams shut again.
this is the J18 surge from hell, deal.
a real pain that. and will happen when you never want it to happen. may seem ok at first, due to this CHAOS setup.
i see no OBD2 data at all , showing water temps SURGING, only rising, best I can tell.
it even runs too hot even with 02 sensor showing super perfect trim......
end surge , cause.topic.
OK Today I pulled everything apart and checked ALL the external tubes and hoses.
I found NO obstructions on any of the pipes. 1, 22, 19,
I replaced the thermostat with a Stant and even replaced the water pump too. The one I replaced it with had impeller 'fins' about 1/4" longer.
I forced water into hose #19 and it came out 22 at the thermostat. I spend 1/2 hour with the front of the vehicle jacked up with the tires about a foot off the ground to make sure I could get all the air out. I went for a ride and recorded the temps and they still are showing high but nothing over 235 now.
So I feel confident that all the 'plumbing' is working as it should. So the next step is to order a 3 row aluminum aftermarket radiator.
I found one.
https://www.ebay.com/itm/3-core-aluminum...0667.m2042
It'll be here Aug 20 and I will install and repeat the whole process. The 3 rows will push the fans back closer to the engine but there is still going to be about 3 inches of space.