King0824

I barely bought my 99 LS400 and I知 doing a coolant flush and replacing my thermostat. The reason I知 doing a coolant flush because the previous owner was using green coolant. So I emptied out all the coolant from the 2 sides of the block and the radiator. So I opened the filler hole and started to pour coolant but it takes it very long to fill and taking it very slowly. Is that normal or is it clogged maybe? because there also was still a little green coolant in the small hole that goes straight down when you open the filler hole.

paulo57509

Perfectly normal. It's super S-L-O-W. Took me close to 30 minutes for the coolant to even show up in the reservoir. Removing the cap from the reservoir helps. I made myself this contraption for the next time I need to refill the cooling system. Remove the TB plug and screw this in its place. I figure I won't have to stand there and dribble 10cc every few minutes into the TB - at least with this thing I can fill the funnel and go do something else while waiting to refill the funnel again.



Bill of Material:

1. Aluminum 14mm plug - McMaster-Carr; Item No. 3494N286; M20x1.5 aluminum Plug
2. 1/8 NPT to 5/16"" nipple - Earl's; plastic nipple (Summit Racing/Jeg's, etc.) or equivalent
3. Length of 5/16" hose - Local auto supply
4. Plastic funnel with 5/16" neck - McMaster-Carr; Item No. 4005T5; 8oz. Plastic Funnel w/Quick Drain Ridges

Yamae

In my case, it took me only several minutes using this method below with the cap open. My funnel just fits the gate size. After filling the LLC, I started the engine and I continued pour it until there came out no more bubbles. This took more me than 20 minutes because bubbles came up a little after a little as the engine warmed up. I also revved the engine time to time. The total job needed me about 30 minutes to complete. The next day I needed to fill up the reservoir some.

TominPT

Yamae, where exactly are you filling the system in your picture? I never noticed a coolant fill port in the top of the engine when I working on the engine last month - but I have only had my '98 LS400 a month.

Yamae

This is it.

paulo57509

This is why refilling is so slow - no vent.

Yamae

I need to add this. My funnel's lower end is cut like this way. The cut makes it faster to fill the LLC. Before doing this, it took more time to fill.