Hey Plane Silly
 

Thanks again for all the help with the installation ideas for the Hardin oil cooler in my Rage. Unfortunately, oil tremperature wise, there is more work to be done since I am still seeing up to 270F+ engine oil temperature during extended WOT runs.

What oil temperatrure do you get from your Whipple 496 during extended WOT runs?

I don't have an oil temp gauge yet. :eek: It is on the list of things to do though. Sorry I can't help you there.

Not a problem. I've been there. What about oil pressure during an extended WOT run?

I don't do a lot of long wot runs. Maybe 1-2 miles at a time. The oil press does drop off some but not to an alarming level. When the weather gets a little warmer here I'll get you some numbers.
I am chasing a high water temp issue, 180* with a 120* thermostat. I am adding a transom water pickup for better pressure and flow. What is your water temp running?

When I asked Whipple what oil cooler , heat exchanger, other modifications is recommended when installing the Whipple kit for the Merc 496 engine in order to handle the additional engine heat I was told: "Sen-dure makes a 1” larger HE which helps significantly. Normally, we do not modify the oil cooler for most pleasure boats. If the guys are “poker run” types, then we have them go to the “extreme” unit from Teague custom marine, which is what we use on 1200hp motors. CP Performance also has a massive one (Hardin Marine 1000hp) that is thermostatically controlled, which is a nice option." Not mentioned in the noted comment but I believe the 120F thermostat is also a recommendation.

Sounds to me like you have a coolant system issue or a bad coolant temp sensor/gage. (PS: I am just a boater that is dabbeling in engine upgrades and not an engine expert) I am still running the stock 496HO heat exchanger and water pump / Bravo water pick up et. al. but do have the 120F thermostat. So our coolant systems are essentiallly the same. I am in the 600 hp range @5800 rpm (versus your 650 hp @ ~5200 rpm) and during similar WOT runs I do not get much over 150F coolant temp with normal running ~130F.

I rebuilt the lower end on mine so I have higher bearing clearances than yours offset by addition of a high volume oil pump so no apples to apples comparison available here. However it seems counter intuitive that you could be experiencing 180F water temp with a 120F thermostat on the 496 and not having low oil pressure numbers do to high oil temperatures at WOT.

What was the lowest oil presssure you recall seeing during a WOT run? (mine currently runs in the low 50's psi at the oil pump with a 3x18 Hardin 700hp oil cooler and it used to run in the mid 40's psi before the bigger cooler addition though the oil then was also below the W50 grade do to fuel dilution and was tested at W40) What is a typical max oil pressure you see cruising with a warmed but not hot engine? (mine cruises in the mid 60's psi). Also the WOT oil pressure at the oil pump (Smart Craft Gage/Merc ECU data) is about 10 psi higher than the dash gage reading with it's sensor located at the top of the engine in the back. Do you happen to know where your oil pressure sensor is located for the dash gage you are reading?

I am in the process of replacing the stock -8 oil lines with -10 or -12 and adding a dedicated 1 1/4" transum water pickup for the oil cooler. Also will likely plug the upper water intake holes in the Bravo that are uncovered during high speed/trim out running.

Do you have a Smart Craft gage installed for multifuctional reading of oil pressure, water pressure, rpm, engine hours and other things?

I am really not going to be much help until I get the boat back in the water. I just don't recall the #'s and I don't just want to through out a guess. I don't have the Smart Craft gauge either. I did hook up a mechanical water press gauge at the heat exchanger and it never got above 10 psi. I think I may have a restriction through the transom assy. I am just going to supply the engine and the inter cooler off of a transom pickup and adjust the water press to around 20. I'll post something in a month or so when I get the boat in the water. Sorry I can't be more help.

The bottom end of my engine has also been gone through but by the previous owner so I don't know all the clearances. Just that it has the Raylar bottom end, Raylar blower came and ported heads with roller rockers.

Tom

In the middle for summer when it hot 90 to 100 My Whipple 496 gets to 160 or so . Maybe a little less. I also don't run wot for very long sperts eather. But never any higher than 160. My oil psi stays arroud 50+ too.

o'yea how is your water ran for the innercooler. I run a pick up off the back of the boat though a strainer and then to the cooler just for the cooler. I did not tap into the system.

My oil temp runs about 180 deg.
My coolant temp about 130 deg.

Chris

When I am cruising that is where I am at as well. Things change a lot At WOT when run for any significant length of time however. Are your numbers at WOT or other?

Hey Tom thanks for no guesses and please do not appologize. I should and do appoligize for asking so many questions. It is a notorious problem of mine.

My Smart Craft gage says water psi at the water pump outlet is 2-3 psi at idle and 43 psi max at some rpm before WOT up to WOT like a pressure relief valve is kicking in. Nobody seems to believe the 43 psi number. The Smart Craft gage reads the data from the ECU that reads the sensors. 'Mercury For Consumers' tech line said that the pressure head at the lower Bravo water pickup is 100 psi at 80 mph. No idea if this is true. Where/how did you tap into the water pressure at the heat exchanger? 10psi sounds real low but I have no basis for that opinion so it is worthless. Did you or the previous owner ever destroy a water pump impeller? Pieces of the rubber can go everywhere and plug up everything. I've had that pleasure.

With ported heads you should be making more than the 650 hp (& heat) published by Whipple for his kit with stock heads. Did the previous owner change the oil pump to a high volume unit?

Please post any numbers that you come up with in the future.

Good luck,

Bill

ttt

I have been through the cooling system looking for blockage everywhere. The only place I haven't been is in the transom assy. With the loss of water flow cooling the engine going to the inter cooler and the power this motor is making it just makes sense to have a transom water pick up. I don't mind a little speed loss with the added drag.(OMG did I just say that)
I don't know about the high vol oil pump but I watch the oil press constantly and have never felt it was low.

Oh, and I take the water press from a fitting I made right before the raw water goes through the heat exchanger.

Tom

So you have the intercooler hooked up to the engine's sea water pump feed. I know very little about Whippled 496 sea water plumbing recomendations but have heard often that supercharger intercoolers are set up with a dedicated transum water pickup. If you have not already talked to Dustin Whipple about this you might want to to get his input.

I was also considering a dedicated water pick up for my oil cooler until I was told of potential for water areation problems with these on stepped hulls like I have.

What oil pressure numbers do you see at WOT?

Would you happen to have a picture that you could post of this heat exchanger fitting installation?

Thanks,

Bill

Hey Bill,
I hooked up a water press gauge to where to raw water goes to the port side header. I put a "T" on the starboard side header feed and ran a water line over to the port header. This allows all the raw water to go through the heat exchanger. Its just something I came up with to try to cool things down.
If I remember correctly my oil press is 60 psi ish at WOT.

I don't think I can put up any pics any more, I let my membership expire.

Did your revised sea water plumbing improve the water temperature?

60 psi oil pressure at WOT, you are fine. I wish I had 60 psi at WOT. I am in the low 50's at 5800 rpm.

If you can still post your comments I think you can still post pictures. I think. But the clock is probably ticking.

Plane Silly,

While trying to post a picture of my Hering prop recently, I noticed that OSO had changed its format to add pictures to the threads. The icon is now above the text box, in the form of a picture box or a paperclip.

Chris

Just brainstorming. How sure are you that you have a 120F thermostat. The stock 496HO thermostat is a 160F and the coolant typically runs up to 180F during hard running. Second thought. If you are staying in the 60 psi oil pressure during hard WOT runs with a replacement crank and bearings (which always have bigger running clearances than the stock) I have real trouble imagining that your oil temps are at all high. If your oil temps are not high then 180F water temperatures should not even be a problem if in fact that 180F value is not erronoeus. Third thought since you are cooling the intercooler with the engine's sea water that is heating up the sea water in addition to the normal engine heat so coolant temperatures should be expected to be hotter. Did you check with Dustin Whipple regarding your issue and the fact that your engine sea water is being used to cool the intercooler?

Bill

10 mile long run today at 90+ MPH - WOT:

62 deg air temp
59 deg water temp

Coolant at 150 deg.
Oil temp at 180 deg.

Chris

My innercooler tee's off of the main water line, right after the raw water pump, goes thru the innercooler, and then dumps out the back of the boat.

After that tee,The main water line goes thru the fuel cooler, then thru the oil cooler, then thru the power steering cooler, then thru the heat exchanger, then thru the headers, and then dumps the raw water about a foot back from the collector flange. This is the way Dustin told me to do it.

He said that if I was having pressure or heat problems with the engine, that I should use a thru hull pickup with a strainer for just the innercooler.

Currently, all the water for my boat is coming from my IMCO drive.

Chris

I have been advised that some of the Mercruiser Racing motors sense the oil temperature at the oil cooler output as apposed to the crank case or oil pump output pre oil cooler. The 180F oil temperature that you recorded has to be such.

I guess the important factor is that the intercoler dumps the cooling water rather than recirculates it back to the sea water plumping of the engine. The question is if that is the same or different than what Plane Silly's engine is plumbed to do.

I dunno... I will check it out when it gets light outside (tommorow)

Chris

Chris,

What is the diameter/size of the T fitting leg that feeds the intercooler? Any pictures of this item installed?

Thanks,

Bill

The t-fitting is installed right after the raw water pump, and feeds the inner-cooler with a 1/2 inch line.

Chris

Well I finally got in the mood to start working on my raft. After doing some more reading on here I got to looking at the hose that goes from the outdrive to the transom assy. It was slightly pinched up inside the gimble. I'm not sure if it was enough to cause my water flow problem but I guess its possible. I think I'm still going to put on the transom water pickup but I would like some input on the location. How far out from the center line can I go. I don't want to disrupt the water at the prop but I would think you need to be as close to the lowest point of the hull while at speed.
I would post some pics but I don't see how to do. I don't have the little paper clip at the top anymore. I will try to post them on another site and link them.
http://crowniehq.net/forum/showthrea...3900#post83900

When you select "reply" to a thread the widow that opens where you type your response includes an "Additional Options" section below which includes a "Manage Attachments" button. Click that and follow the instructions to attach whatever.

Mine doesn't have the additional options section anymore. I think it is because I let my paid membership expire.

Plane Silly,

What is going on with your Rage upgrades?

I am holding off on the transom pickup until I do some more testing. Bob L recommended that I block off the 4 upper holes on the outdrive and see if that helps my press some. The weather has been crap here so it looks like another weed before I can get her in the water. I would still love to see a pic of a transom pickup on a Rage.

Plane Silly, anything new?

Still haven't had her in the water yet. I did block off the top 2 sets of holes on the drive water inlets so that's what I will be checking first. I'll let you know.

Hey Plane Silly, any new test results on your Rage?

Well, I took a water press reading at the raw water pump right where the sensor is and it sure seems low. At 50 mph it was only about 10 psi, at 80+ it did get to around 22 psi. Motor still runs around 170* even though I have a 120* thermostat. And yes I have replaced the thermostat and tested it in hot water. Still seems like I have a flow issue.

I was concerned that the 43psi+ sea water pressure I get at WOT (5800 rpm) was incorrect, so I have been asking around a lot. Bob at Dana Marine did not know what was the normal pressure for the 496 but called a guy that installs a lot of Dana exhausts on Mercs and tests water pressure on each install. He stated that Merc rates that system from 38 - 50 psi at WOT (5100 rpm stock) so my 43 psi at 5800 rpm is normal and maybe on the lower end based on max rpm for stock 496HO's.

What rpm's are you getting the 10 psi and the 22 psi at?

22 psi was around 5000 rpm and don't recall 10 psi but I think it was around 3500.

For reference with the stock sea water plumbing my sea water pressure is 22 psi @3500 rpm, 41 psi @ 5000 rpm and 2-3 psi @ idle.
With the recent addition of a 5/8" dia sea water dump hose 'T'd' into the out let side of the oil cooler water hose (to increase cooling water flow rate through the oil cooler) the sea water pressure dropped to 15 psi @ 3500 rpm and 30 psi @ 5000 rpm and 1.5-2 psi @ idle.. Sounds like yours is low for the 496HO. My coolant still stays in the 140F's during WOT running even with the addition of the water dump hose.

How many hours/seasons on your sea water pump/impeller? Ever get into sandy/muddy water with the lower unit? I understand that the stock brass body water pump can get chewed up pretty quick if sandy water runs through it.

I have rebuilt my sea pump with the stainless plate and new impeller so it should be good. I have a big event at Cumberland this week so I may just leave things alone right now but it is looking more and more like I am going to have to install the transom water pick up.

I figured that you probably had. Well logic would seem to say that if your water pressure is that low at the rebuilt water pump output it has to be between the Bravo and the pump because restriction down stream of the pump would show higher pressure at the pump and lower down stream of a restriction.

I probably mentioned it before but I have been warned by one very experienced person that steped hulls (Heat) can have aireation problems with transum water pick ups that also result in cooling problems. Hopefully someone out there has a proven successful transum pick up mounting location for a Rage. Good luck and keep us posted.

Thanks for all of you input Rage. I don't want to put the pick up on but I am running out of options. I may pull the drive off and see if I can find some kind of restriction.

Thanks again,

Tom