Pressure Drop on 2-Hole CLE

**Dave Strong** · 04-28-2016, 09:23 AM

I was under the idea the water tube was cast into the mid?

Dave

**Onetime** · 04-28-2016, 10:00 AM

Everything I was reading here was all to be expected except for this cast in water tube without a copper tube. Never seen anything like that.

The difference in pressure is spot on. The two hole CLE was originally for the 2.4 hi-perf engines. When the 2.5 came out in 92 they first used the two hole CLE and it was marginal. then Merc upgraded to the four hole CLE to get more water volume through the block. This is when the 3/4" water tube came out also.

**tlwjkw** · 04-28-2016, 10:07 AM

"no brass (as he called it)/copper tube".... thats what he's sayin' sounds like ta me... if so, callin' that **** out.... hell, they don't even do that ta factory sponsored hot rod....

tha 3/4 didn't show up till tha sporty came out.....

**WillySteve** · 04-28-2016, 10:46 AM

The area in the downhousing casting has a rubber seal inside to seal the top of the pump housing to the water inlet inside the downhousing!
Now that said, I have never had the down leg off and apart but this is what I'm seeing from the bottom!

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**Dave Strong** · 04-28-2016, 11:17 AM

Things are coming to me now. Had 91 245hp 2 hole CLE. Ran with 3-4 psi at idle 16- 17 at WOT. After the first year the tuner broke, was sent a new exhaust plate and tuner that they said provided more water flow to the tuner to keep it cooler and prevent future breakage. After replacing the water press dropped to 1-2 psi at idle and 12 psi at WOT. Merc said as long as the temp was good it was OK.
3/4 tube came out in 93-94 on the 4 hole CLE. Thinking your press is low because of a similar deal.

Dave

**tlwjkw** · 04-28-2016, 11:25 AM

whats that above tha rubber seal in tha down housin'?.....

Dave, had several "90 ta '94 hot rods that came with cle's ( first 2 hole then 4 hole) and they ALL had tha 1/2"... maybe was just luck of tha draw right before tha sporty came out! maybe another one of those "lets use this stuff up" deals

**WillySteve** · 04-28-2016, 11:40 AM

Maybe so? Do you remember if the waterpump nipple went inside of the 3/4 tube, possibly inside a collar with a square cut o-ring seal?
I have pushed, pulled and yanked on the dang thing and never got it to move even the slightest bit.....this is why I say it appears to be cast in but it is a possibility it's just stuck solid from so much carbon through the years!
When you bolt up the LU to this housing there is no guiding the water pump, it bottoms out on the housing inlet dead nuts!
Yesterday my water pressure was 4# at 4500rpm but was certainly pumping water out the right pee tube coming from the poppet cover. I can't see the right side coming off the top of the heads. I stopped twice and the expelled water was warm, maybe 100 degrees, but definitely not hot!

**transomstand** · 04-28-2016, 11:42 AM

Originally Posted by WillySteve

The area in the downhousing casting has a rubber seal inside to seal the top of the pump housing to the water inlet inside the downhousing!
Now that said, I have never had the down leg off and apart but this is what I'm seeing from the bottom!

Plastic guide tube could be melted to the copper tube with the water pump seal stuck in it. This would make for a poor sealing situation.

**WillySteve** · 04-28-2016, 12:02 PM

OK, It's the 3/4" tube which is evidently stuck in the housing. Nothing but the tip of the collar is sticking out from the bottom of the housing!

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**tlwjkw** · 04-28-2016, 12:02 PM

Originally Posted by WillySteve

I have pushed, pulled and yanked on the dang thing and never got it to move even the slightest bit.....this is why I say it appears to be cast in but it is a possibility it's just stuck solid from so much carbon through the years!

mystery solved! tha tube is held in place with a compressed (by little retainer) grommet in tha adapter..... its got a regular "copper tube" in it just all tha rest.................

plus what tha "heathen" said.

**Onetime** · 04-28-2016, 03:22 PM

The bigger tube did come out with the four hole CLE long before the Sportmaster. Been over 20 years but still certain of this. Sometimes the four hole would be used as a replacement for the two hole and would just use the 1/2" water tube pump housing. Four hole CLE lower units sold as a replacement part came with both water pump housings.

Willy, you need to be careful here as it sounds like you might have put a 1/2" water tube lower stuffing it into the 3/4" adapter that sits on top of the water pump.

Air in the water and water leaks on the pressure side are very detrimental to your engine living.

**WillySteve** · 04-28-2016, 05:15 PM

The 4-hole that came with my engine had the very same waterpump housing as the 2-hole I'm running now! From what I've seen, the difference is that on the 1/2" pipe mid, the pipe goes inside the snout on the WP housing and on the 3/4" pipe mid the collar on the end of the 3/4" pipe goes OVER the WP snout itself....Same Waterpump, different way to connect!

**tlwjkw** · 04-28-2016, 05:33 PM

They "both go inside".. tha 3/4 uses a different pump housin' and are real expensive compared to tha 1/2" housin'.... don't make a hill a beans when tha 3/4 came out but they gotta match one way or tha "other"....

doubt he changed it cause he though it was made into tha down housing!

**WillySteve** · 04-28-2016, 09:18 PM

My engine NEVER had the 3/4" top pump half, (46-847710T 1)! No one has ever touched it but myself and I've always used the very same top halves that came on it.....a Standard top half that fits inside the existing pipe collar, (the existing collar slips over the standard pump's nipple)!
I have measured this several times through the years with a depth gauge, just to make sure all fits together properly as like most others, not having that tube sticking down to line up as you raise the LU always just don't feel right!
I'm gonna yank it again tomorrow.....with all this, now I'm worried again, even though I know I ain't slipped that much yet!!!

**WillySteve** · 04-29-2016, 05:04 PM

Originally Posted by WillySteve

My engine NEVER had the 3/4" top pump half, (46-847710T 1)! No one has ever touched it but myself and I've always used the very same top halves that came on it.....a Standard top half that fits inside the existing pipe collar, (the existing collar slips over the standard pump's nipple)!
I have measured this several times through the years with a depth gauge, just to make sure all fits together properly as like most others, not having that tube sticking down to line up as you raise the LU always just don't feel right!
I'm gonna yank it again tomorrow.....with all this, now I'm worried again, even though I know I ain't slipped that much yet!!!

OK, I pulled the LU this morning, haven't got pics yet because of the weather turning bad but I did remeasure everything!
The tube in the downhousing is a 3/4 and has a larger collar on the bottom of it. The top of the standard pump housing is the exact same height as the depth of the 3/4's collar! OD of the standard pump housing is the same as the ID of the collar!
This is how it came from the plant in 1995!
I will dress it with good ol RTV when I reassemble!