Rhythm and Blues

Afternoon fellas, this is a cross post. Hope its ok.

So, this is a giant can of worms I understand that but I'm interested to see what's "working" for most people up here in the Ocean water in the Northeast in the interests of developing a good starting point base line. I've had my Café for a couple months but leave for work every two weeks so I've only had it in a couple times. Once in the lake for a couple hr shakedown, just to make sure everything looked good, then in the ocean for a couple hrs, this is where I'll usually run. So, I don't have a lot of running time data yet. When we ran in the lake about a month ago we were seeing a max h20 psi of 25 but had trouble building any engine heat, saw maybe 100-110ish when "warm". Motors are CMS NA 572-w- stainless marine crossover/bypass, Hardin Marine Cyclone headers, 2"x16" oil cooler-w-out t-stat, all 1-1/4" raw water hoses, Bowtie blocks, Brodix aluminum heads and intakes, drives are Imco Xtream SCs spinning 26p B1s. Its raining today and the boats covered, I'll post the oil cooler AN plumbing sizes when I can uncover it, I'm thinking their -6 or -8. The previous owners ran the boat down in nice warmer South Carolina water and had 3/4" restrictors in the T-stat housings, boat apparently ran 140ish water temp (kinda ideal) so we ran it that way in the lake for the shake down. After thinking (overthinking) about it I threw in a set of SS (drilled 5/32 x 3) thermostats (non High flow) before we put it in the ocean. Everything looked good initially, boat came up to temp and ran 140-150, water psi was 20ish psi at cruise speed 3500 rpm. We stopped for a drink then headed back; about 1/2hr into running back the stb motor decided to get a little warm, I saw 230-240 so we slowed down and I took a look (brought my infrared thermometer), couldn't see any glaring differences from the pt side motor to the stb motor (various spots around the motor and headers) in terms of temps but flow from the tattle tale was less on the stb motor; I thought maybe I got a steam pocket that showed up on the back of the intake manifold where the temp sensors are. Average water psi for me at idle with both the restrictors and the t-stats is between 0-5psi. Water flow in the strainers appeared about the same at idle, and the pumps were the same temp too (Hardin gen 4 SS seawater pumps)
We let the motor cool down then ran the rest of the way up the river w/out any issues but with slightly less water pressure on the gauge on that stb motor. I took the boat to the lake and flushed it, still showed less h20 pressure but I really wanted to flush it with those t-stats in it so I had to get it up to temp and knew I wouldn't have been able to do it on the hose at home. After I got it to the house I pulled both water pumps and the stb motor had one of those Globe blue run dry impellers in it, I had read a lot about these here on OSO; seems general consensus is they garbage, maybe or maybe not but I thought I had found the smoking gun.. I called Hardin and they confirmed all their testing and data for the pumps was taken with stock merc rubber impellers, he went on to say that those globe run dry impellers don't work very good in their pumps and that they dealt with a ton of warranty issues with ILmor because they ran those globe impellers in a big production run of the V10s. Soooo, I installed new merc impeller kits in both pumps and I have gone back to a 3/4" restrictors (out of fear, lol); haven't had the boat back in the water yet, looks like rain for the rest of my life up here... Anyway, I have a set of high flow 140 t-stats in stock 140 Degree Brass Hi-flow Marine Thermostat (drilled with 1 single 1/8" hole) and am wondering if I should throw these in to start testing again? Maybe before that drill two additional 5/32 holes and open up the current one to 5/32 as well. Currently the motors do not have any oil temp gauges (I will change this, have no idea why they don't, seems pretty critical) hopefully I can shoot the oil filter (pre cooler) with the IR gun in the meantime to get an idea of temps. I claim to be no expert what so ever, this is all new to me and would really welcome some constructive feedback. Do I need to run an oil t-stat setup, restrictors, t-stats, circ pump instead of x-over/bypass, psi reliefs at the back of the manifold?.......


Anything you have to say I'd appreciate... Thanks.
PS, I may double post in the Northeast section; hope that's alright...

widowmak

I run 100-110 water temp with 180-200 oil temps. Just enough heat to rid the oil of condensation and perfect temp to make max hp.

veloc410

I was running 160 temp this year I noticed some light bronze color on some valve stems. I don't think you want to run to warm. The heads are running hotter than water temp is showing because the engines are under constant load. Also causing the valve stems to dry up. I'm struggling with figuring what temp is best and also think I need more oil to guides with different seals. If you run to hot your valves will warp. That happened to me last year. My engines were to hot, I didn't know because gage was reading 140 at thermostat housing but engines were well over 200. My sender is now in the intake. So now accurate readings. Anyway ran 160 this year and don't like the results. I have iron heads. Probably better results with aluminum. I definitely think you should NOT go over 140 actual engine water temp. I'm going with 120 t stats next year. 30 weight oil and different valve seals. And hopefully not have to touch these again for quite a while. Any other input would be great info for everyone.

veloc410

are you running water thermostats. If so what are you using

veloc410

i found my incoming fresh water was dead heading the hot water trying exit the engines. I routed all hot water exiting engine intake directly out through the transom via water dumps. Nothing but cold water feeds the engines and exhaust manifolds. The exhaust is much cooler and engine temps are constant now.

getrdunn

Always seemed like my water temps over the years stayed the same at 140 with 190-220 oil temps depending on how many miles I'd leave it pinned. The 496's I built with x-over I installed water temp sensors in the block drains rather than intake. New builds going to do the same including oil temp sensors in the pan.

getrdunn

I reread your OT and think your going about it right and on track. Key is your paying attention and wanting the best care and conditions for your engines. Many it seems end up going back to stock circulating pump and t-stat housing however i personally feel after some time and testing you can get your set up dialed in with a little time. I would however run oil stats on any marine engine even in a higher hp sc build where your building a lot more heat.

the size of my old bypass hose was 10 AN with a 140 stat with 3 - 3/16" holes. Running one on the floor stand without holes in the stat I had a lot of fluctuation and before I knew it water temp was at 200 plus however after a short period of time dropped down below 140. Again you'll get different opinions but I wouldn't run without oil stats no matter what. Oil temps are crucial and if cruising long distance at 3k plus/minus you'll find oil stats won't even open.

No no need for any expensive one either. Earls makes a nice billit one for 100.00. All you need and easy install.

Also over the years from what I've read and personal experience you can have two nearly identical engines and they can still react differently. What works for some doesn't for others. But again I think you going about it the right way. Get some oil stats and temp gauges. And you'll be fine

Full Force

I tried them Stats, they gave me pressure issues and never opened... I went back to no stats and been fine since, I see 160-200 oil temps on cold side after cooler water is 110-130 tops... no issues for years, I had issues when I tried to make it "better"

Rhythm and Blues

Understood. I wasn't having issues with the motors being too hot at all. The issue up here is building temp. This summer I went through 3 sets of thermostats and 3 sets of restrictors. Once I figured one particular orifice size was fairly acceptable I was getting lube oil temps up enough, never milked the engines but cooling water still wasn't registering on the gauges. The other issue was running the boat hard the non power steering engine PT side was making like 22-25 psi water pressure and pushing some water from the HGs. Dumps for that issue are in the future.

veloc410

https://www.summitracing.com/parts/sww-122260/overview/

i used this cheap analogue gage to double check my temps. Comes with 6 ft flexible capilary tube and fitting at end, I used a reducer bushing in the intake manifold to plug it in. 15 bucks. They have better more expensive models if you want to mount it permanent. They state to be careful with tube and try not to bend it at the ends. Not sure where your temp senders are but this what helped me trouble shoot and nail down my temp issue. It will at least give you second way to monitor your temps. I imagine you could check your oil temp with it also. I would not trust what the t stats housing reads it has mixed water in it. My sender were in the housing and we're showing around 130 -140 but when I installed the analogue gage in the intake manifold it was showing 210- 220 just idling. I then moved my senders to intake manifolds and they read within 10 degrees of the analogue gage from summit