Starboard vs port manifold temperature?!

[psousa]

Hi!

Today, after about 6 miles running around 3k rpm, I docked and with no particular reason I start looking for engine and cleaning it. I noticed that starboard exhaust manifold and elbow is so hot that I can't stand my hand for more than a couple of seconds while those at port side is only a little warm and I can stand my hand on it as long as I want.

Looking for my manual cooling diagram I can't find a reasonable explanation for this huge temperature difference... any idea?

V6 alpha 2
Salt water cooled

[mmwjr]

Use a IR thermal sensor and take readings of both manifolds. If one is hotter than 160 F its to hot and should be inspected and may need replacement.

[psousa]

I'll buy one this week but I suppose it's higher since 160F = 71C and 71C is tolerable, as far as I know...

Any way, I'll post results when tested.

Ty

[mmwjr]

Also take a reading of the coolant hoses feeding each manifold to see if there are being feed water of the same temp.

[psousa]

Here are readings made today morning.

After 20 minutes engine running (5 heating, 10 inside marina at low speed - marina floodgates still closed because of tides :\ - 5/10 minutes stopped and then 5 minutes flushing with fresh water) I observed:

1. starboard side is about ~20F to ~30F hotter when compared with port side
2. the hottest point is in starboard manifold, on stern section (the colder zones are located at stern half of elbows)
3. starboard hoses are always hotter than port hoses (but became even hot after engine stop, which means water is circulating while running, I think)
4. all starboard side of thermostat housing assembly is hotter than port half, and the stern zone is the hottest zone (where water get inside, coming from engine, right?)

Temperatures (F) - picture label:
1A: 145
1B: 159
2A: 112
2B (manifold - not gear lub hose): 129
3: 125
4: 119
5: 126
6: 120
7: 124

Another detail: when I press the biggest cooling hose (the one which links thermostat housing assembly to engine water circulating pump) I hear some kind of cracks... could it be parched and losing rubber? It seems nice from outside!

Also, took some pictures of water flushing from propeller (while flushing circuit with fresh water). Do you think the flow seems ok (the tap was half open)?

Also, took some pictures of water coming out from propeller (while flushing circuit with fresh water). Do you think the flow seems ok (the tap was half open)?

Another question (out of topic): I always flush cooling circuit with alpha ii all down because I saw we must do it (in the internet). But, if NOT engaged, can it really cause damage if we run engine while in trailer position?

Thank you

[shrew]

It would be more effective to measure the temperatures after the engine has completely warmed up and is running. Possibly running under some RPM. The temperatures you're reporting seem way too cool.

[mmwjr]

To start with the good news none are over 160 F. As shrew said I would prefer taking temp after running on plane for 30 minutes.

My comments.

#6 is the raw water supply and I would expect this to be under 100 F put since it runs across the top of the engine it may be getting heated up.

#7 depending if you pointed between the t-stat and hose #6 you can get a mix of engine water and raw supply so the number will be low. Need to point directly at t-stat of intake manifold where t-stat installs.

2B is the power steering hose but you temp is actually the manifold which makes sense with the reported number.

#3 is the water supply to the starboard manifold and #4 is for the port. The starboard is 6 degrees hotter which is not uncommon.

Not sure I understand where 1A and 1B are pointing too as they seem to be the same but have different readings.

[psousa]

Thank you both!

Shrew: you right! Made it today.
Moment: 2b arrow is wrong. Is pointing to manifold. 1b is all poiting to hot manifold. Line is dotted and dashed because is poiting behind riser.

Now I have good and bad news.

Good news: temperatures on open running are good. Ran 15 minutes @3,5RPM and no hot spots unless one single spot on starboard manifold which shown 163F but it's inside thermometer error margin. Returning to marina few minutes ago, I made 30 minutes @3,5RPM (my regular speed) and temperatures are even lower (water temperature is lower now).

BAD NEWS:
I'm being towed because I can t engage forward speed. After retur to marina I decided to stop nearby to take advantage of the end of the day. Can t engage forward anymore. Ask for marina help and they are towing me. :/
When I engage quicksilver 3000 throtle forward, engine does not engage and propeller keep stopped. I try to engage backward and I can't. Is stuck. If I use middle button I can I put throtle to forward and backward.
If I try to engage, forward do nothing. Backward is stuck.
In fact, after backward engage, it was always difficult to engage forward again. I must to give a smal touch to red button and throtle so I can engage forward again. Now it fails completely!

Do you think this is a quicksilver 3000 throtle adjustment issue or a lower unit issue? :S

[mmwjr]

So exhaust temps are fine but now a shifting issue.

Let me see if I am following you.

With the center button pressed to disengage the shift cable you can move the shifter into both forward and reverse positions, correct?

When trying to shift into forward the shifter moves into forward but no forward gear, correct?

When trying to shift into reverse the shifter will not move into that position, correct?

Sounds like the shifter or the drive has failed. Try disconnecting the shift cable at the shift bracket on the starboard elbow and see if the shifter works. Then disconnect the lower shift cable and see if you can shift the drive by pushing and pulling on the end of the cable.

[psousa]

I forced reverse and it looses but Now i can shift forward and reverse, with red or middle button pressed but drive does not engage anyway! Damn!

[psousa]

Well, disconnected lower cable and I can move it forward and reverse with my hand and does nothing :/
When moving shifter only give or take gas to engine. Can't engage it :/

[mmwjr]

Originally Posted by psousa

I forced reverse and it looses but Now i can shift forward and reverse, with red or middle button pressed but drive does not engage anyway! Damn!

Remove the shift cables and test as I defined in my previous post.

[psousa]

Hi Mmwjr!

The cable is out. I can move it freely for both sides. Does nothing.
Unfortunately I think I have to pull the boat out of the water.

[mmwjr]

You can call me Mike

Not sure I know what you mean by both sides moves freely.

Does the shifter move freely into forward and reverse with the cable disconnected? If so I would think you have an issue with the drive or lower cable.

[psousa]

Mike, I mean i can pull and push (like if shifting forward and reverse) the inside cable and nothing happens. I hear nothing too. It seems loose since it moves very smoothly, I do not need to force to make it moves through it's course, but I can't completely pull it out or push it until I loose it. Seems something disconnected on the other end of the cable (inside drive).
It seems out of my DIY capabilities. Tomorrow i'll talk with marina mechanic. hope something they could fix quickly :/

[mmwjr]

Next step would be to remove the drive and see if the shift lever on the transoceanic assembly moves when pushing and pulling on the cable. If this checks out then it's an issue with the drive.

Google some you tubes to get a better idea of what I am talking about even if you have a mechanic fix it it's good to understand when discussing it with him.

[psousa]

Thank you for the support and youtube tip, Mike!

She's out and I'll update on new details, so it could help others. I also try to change the topic title to be more precise (update: I can't change it, sorry!).

Meanwhile, a picture of the beast and the lady!

[psousa]

Hi!

Fortunately is not a major issue. A bolt was missing. I'm not sure exactly which bolt is since I was not there when they pulled the drive out, but the only bolt which seems to be touched is that bolt in the IMG_1981.jpg picture.

Now we are waiting for someone from the shipyard to wash the hull and the drive and then the gasket will be replaced, the drive will be fixed back again, make some shift tests and then she will be in the water again. Hopefully at the end of the day, maybe tomorrow (also depends on tides).

[mmwjr]

So the set screw came out, easy enough fix.

Never had that happen if anything I cannot get it out and have to drill it.

Glad it was a quick and cheap fix.

[psousa]

She's back to water! Running like a charm.

It was not so cheap for a single bolt (550eur at the end) hehe

Well, everything is now ok!