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Expert troubleshooters needed for a frustrated boater

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trojan10

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Thanks in advance for your help. I have a port carbed, fwc, crusader engine with about 900 hours that has a vd tranny slightly overheating with a little oil coming from the over pressure relief valve and some steam in exhaust. Over a two year period have replaced-oil cooler, risers, raw water pump, freshwater pump, new transmission oil lines to cooler, and finally we replaced the Velvet drive transmission. The temp on the tranny is 40 degrees higher than starboard and the temp at the thermostat on both engines is within a few degrees of each other with IR gun. As stated there is definitely steam on port side exhaust and we feel it is a flow issue but just can not seem to find the problem. Have also swapped out hoses so that the stbd raw water pump went to port and vice versa-no relief. Has anybody ever had an issue with output side of cooling flow and has that been an issue. The overall operating temp on port side is about 175 compared to 160-5 on other side with console gauges. Thanks again for your help
 
It appears you have replaced the likely suspects. You mention 40 degrees higher; what is the cruise temp of the tranny? What is the temp. drop thru the cooler of the oil? This is a 72 series with reduction? What are you using for oil and how much? The ones I'm familiar with have a vent at the top, but no "relief valve".
 
diver_dave said:
It appears you have replaced the likely suspects. You mention 40 degrees higher; what is the cruise temp of the tranny? What is the temp. drop thru the cooler of the oil? This is a 72 series with reduction? What are you using for oil and how much? The ones I'm familiar with have a vent at the top, but no "relief valve".
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The cruise temp is still within the safe operating temp of the transmission but just higher than normal and therefore I believe why it is venting (you are corect-vent at top)out a little oil from top of "vent". The tranny is a 1.91:1 velvet drive transmission with dextronIII tranny fluid and we fill as described in book-run up to 1500rpm for a couple of minutes and then check to make sure it is at described line on dipstick. I do not think it has anything to do with tranny though as we replaced with another velvet drive transmission and it is still exhibiting same issues before replacement. At this point though I am befuddled and looking for any input.
 
Is this a 10M Trojan by any chance? Just a wild guess on my part :)

If so, I have the same boat and happy to take any temp measurements with my IR gun if that would help. Same drivetrain with a little under 800 hours on mine.


Bob
 
bobct said:
Is this a 10M Trojan by any chance? Just a wild guess on my part :)

If so, I have the same boat and happy to take any temp measurements with my IR gun if that would help. Same drivetrain with a little under 800 hours on mine.


Bob
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I appreciate the offer, but i am curious if you have ever had any problems with the output side of your exhaust system and yes it is a 10 meter express. I believe it is a flow rate issue and have replaced or checked everything on input and wonder if it is an output blockage issue. We also have an IR gun that we use and check against our stbd engine to see if any difference.

Jim
 
It could be the tubes in the heat exchanger are in various states of being plugged. Pull off the end plate for inspection. I agree; steam means low raw water flow. I would think the exhaust to be an unlikely candidate, especially if the engines run WOT OK.
 
My Trojan 350 (1995, 600hr, 454XL) has had steam since day one. Many threads on steam. My VD gear box temp gauge on the helm barley moves. I don't know the temps on the gauge. I'll have to go onboard and look at the gauge. What should it read?
 
I dont have the actual numbers in front of me so I am going from memory, but i believe the safe operating range is 145-180 f. If your temp gauge is barely moving then you are lucky and I would not worry about it.
 
diver_dave said:
It could be the tubes in the heat exchanger are in various states of being plugged. Pull off the end plate for inspection. I agree; steam means low raw water flow. I would think the exhaust to be an unlikely candidate, especially if the engines run WOT OK.
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I agree with you but I believe we cleaned out and then changed out port to starboard echangers with no luck or change in problem. We are having problems with the engine after 3200rpm's it bogs down and misfires which we believed to be a distributor or fuel issue-boat runs fine from idle to the 3200 rpm though. One problem at a time as they say. When you said especially if the engines run WOT ok are you thinking that it could be an exhaust issue if I did have a problem with WOT? My frustration is that we have done most logical things to this engine and are still fighting this issue.
 
If you can get a 0 to 15 psi gauge, you can install it in the raw water 1/8" NPT fitting on the bottom of the heat exchanger. That port is usually used for winterization draining. Run the engine, in neutral to 3000 rpm and notice the pressure. Compare this reading to the other engine. This should give a high reading if the back pressure is high, coming out of the HE. You will see some vibration in the needle due to the exhaust pulses, a liquid filled instrument is best. If this reading is LOW, then you will have to work backwards towards the pump to find the problem.
Was the pump replaced with a NEW one?
 
diver_dave said:
If you can get a 0 to 15 psi gauge, you can install it in the raw water 1/8" NPT fitting on the bottom of the heat exchanger. That port is usually used for winterization draining. Run the engine, in neutral to 3000 rpm and notice the pressure. Compare this reading to the other engine. This should give a high reading if the back pressure is high, coming out of the HE. You will see some vibration in the needle due to the exhaust pulses, a liquid filled instrument is best. If this reading is LOW, then you will have to work backwards towards the pump to find the problem.
Was the pump replaced with a NEW one?
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Wow-that is a good idea. the raw water pump was replaced with a new one. Thanks for your input
 
trojan10 said:
Wow-that is a good idea. the raw water pump was replaced with a new one. Thanks for your input
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Its been a couple years since I did this test, I recall about 4psi being a typical, mid-throttle reading. You can use a hose to the gauge to get it in a better reading position.
 
Hey Dave,

Thanks for your input it is very much appreciated. On a side note my good friend just purchased a 50 Cary. Do you own a Cary boat and is that the same make? This boat is pretty spectacular with triple diesels and arneson drives. The boat is a beast that barely moves when hitting wakes.
 
The 50 is a beast, like you say. It's the boat you want for that havana, nassau, miami run (breakfast, lunch, and dinner). I'm very happy with my 32'. They were all made in Miami, although I believe Mr. Cary sold before the 50 was introduced.
ph-g022-400.jpg
 
thing that gets me is the gear temp difference of 40 degrees....assumes this is present with either (original or replacement) gear?

If so, I'd look for a major air leak in the raw water pump's intake line or a marginal adjustment on the control cable connected to the gear.

In addition to the pressure gauge, actually measuring the raw water pump's product is a known high value data point when debugging heating issues. Another "trick" is to install a short clear piece of PVC hose - any air bubbles are easy to see thru the hose.
 
makomark said:
thing that gets me is the gear temp difference of 40 degrees....assumes this is present with either (original or replacement) gear?

If so, I'd look for a major air leak in the raw water pump's intake line or a marginal adjustment on the control cable connected to the gear.

In addition to the pressure gauge, actually measuring the raw water pump's product is a known high value data point when debugging heating issues. Another "trick" is to install a short clear piece of PVC hose - any air bubbles are easy to see thru the hose.
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Thanks for your input. We had heard about that control cable adjustment not letting tranny fluid through if not fully engaged and actually had that piece tested and did go through adjustment troubleshooting with no luck. Also the problem showed up on both sets of transmissions put on that port engine so it lends me to believe that we are back at a flow rate problem and need to pinpoint. I think you are correct in starting at the volume measurement with the pump and compare to the stbd side engine. What do you do to see if there are air bubbles, attach clear hose to end of raw water pump to the oil cooler? On a side note two years ago we had some growth on that side of the input clamshell that blocked the seacock to a pinhole. Once we found this we obviously chipped out and thought our problems were solved. I am thinking after talking with someone that maybe that the hoses to the raw water pump have been affected someway after this from the extreme vacuum and are still wreaking havoc on flow rate. I will keep you posted
 
Hoses can delaminate and block flow, as well as the more obvious kinking. You reported the problem continues even when using the other side pickup system is used, I think. Is there an internal raw water strainer? Is there a crash bypass?
 
trojan10 said:
Hey Dave,

Thanks for your input it is very much appreciated. On a side note my good friend just purchased a 50 Cary. Do you own a Cary boat and is that the same make? This boat is pretty spectacular with triple diesels and arneson drives. The boat is a beast that barely moves when hitting wakes.
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There's a Cary 50 Sport Fish rotting away in Trappe MD just at the Choptank River. Some numbnuts put a bracket for quad OBs on it, so it would need all new everything. I'm sure it would go for cheap.
 
diver_dave said:
Hoses can delaminate and block flow, as well as the more obvious kinking. You reported the problem continues even when using the other side pickup system is used, I think. Is there an internal raw water strainer? Is there a crash bypass?
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I am not sure what you mean by crash bypass, but we do have a groco sea strainer. You are correct that we used the other side pickup system-so many things I forget sometime. That was why we thought it might be a blocked outflow problem that is reducing flow through the system and to check the pressure at the heat exchanger as previously recommended. However at this point it might be prudent to just go through each connection of raw water flow and check everything over again starting at how much the raw water pump puts out in volume.
 
trojan10 said:
I am not sure what you mean by crash bypass,
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A "crash" bypass is a valving method of pumping bilge water into the engine, rather than outside water. It's another point of failure, in that the added valving could bring in air. If the valving is below the water line, any leaks at rest should be apparent. Same for the raw water strainer. Leaks at that Groco cover O ring should show at rest IF the unit is totally below the waterline. That cover O ring should be inspected; I should say that mine are well over 12 years old, and the covers come off frequently.
 
I never thought of that, I have the Groco SVS (?) valves which allow you to do a fresh water flush out which I do at the end of every weekend and the can be emergency pumps (using the engines) if you had a catastrophic failure.

What I didn't think about was the potential for those to allow air into the system. I guess I will grease up the o-rings as they suggest.

Bob
 
I'd concentrate on the raw water side, from the inlet to the oil cooler, at least initially. Since changing the suction system doesn't change the system's behavior, I'd start with the pump's delivered volume. Many posts ago, i attached a PDF that showed what the stock size pump should deliver. That, a bucket, and a stopwatch will get you going on that datapoint.

I use a short length of 1.25" hose, usually before or after the oil cooler, to check for aerated cooling water. Anywhere you have access will help. Sometimes, you have to be creative to get that clear hose where you need it.
 
Ok so we did extensive troubleshooting today with no luck. Started with the pressure gauge on port heat xchanger and it was actually lower PSI than the stbd side. Then we did the bucket test and the the port side had more volume of water and filled the bucket in less time than stbd.-go figure. So I am now thinking that all the change outs we did on the port side obviously made for less resisitance on the raw water flow of the port side, but left no glaring smoking gun to fix this problem. We then changed out the outflow of the stbd engine water pump and ran a hose over to the input of the port oil cooler and vice versa with no change except for the predicted less flow on port engine. The one glaring difference was the temp on intake manifolds was 20 degrees hotter on the port side than the stbd. side? We did a compression check and all the cylinders were around 125 and within 10 percent of each other.The other question we had was if the transmission lines on the port engine were the same as the stbd. If the stbd. transmission rotates one way and the port engine tranny counter then does that mean the oil lines from tranny should be set up differently than stbd. Could we have mistakenly switched tranny oil lines on port side so they are now backwards even though they are set up exactly as stbd? Arghhhhhhhhhhhhhh
 
The tranny lines should be plumbed the same, port and stb. Since you have an IR gauge, measure at the oil cooler the temp in and out of the 4 oil lines at cruise. I'm having trouble with the fact that the tranny is overheating and not the engine. It's not pointing to a raw water cooling system problem. One my second post, I'm asking for a temp drop of the tranny oil thru the U cooler. This is a critical measurement. Too high a temp drop indicates too little oil flow in the tranny cooler circuit.

Is there a kink in the tranny oil hose? Exactly how much oil is in the port tranny?
 
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diver_dave said:
The tranny lines should be plumbed the same, port and stb. Since you have an IR gauge, measure at the oil cooler the temp in and out of the 4 oil lines at cruise. I'm having trouble with the fact that the tranny is overheating and not the engine. It's not pointing to a raw water cooling system problem. One my second post, I'm asking for a temp drop of the tranny oil thru the U cooler. This is a critical measurement. Too high a temp drop indicates too little oil flow in the tranny cooler circuit.

Is there a kink in the tranny oil hose? Exactly how much oil is in the port tranny?
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The tranny oil hoses were just replaced with new ones that we had made up to rule that out. At this point I can not see how this could be raw water flow issue either with all the tests we did, however we do get steam out of that engine if that means anything. Could there be something wrong with the way the new risers were put on or anything in that area that would cause the temp diff. in the intake manifold between the two engines? May this be the cause of the steam and the tranny oil issue? As far as the tranny, we replaced with another that was working and duplicated the problem so It has to have something to do with the original engine. I am thinking we should just change out oil cooler again to be sure it is not something in there that is causing this with a spare. You have me thinking though if it is not the flow rate on the raw water side then could it be the flow rate of the oil through the cooler. Maybe something in the oil cooler is blocking flow of oil through the cooler?
 
did you use the correct gaskets at each exhaust joint? Each gasket in the correct orientation? Could be a factor in the 'steam issue' but doubt it has anything to do with the elevated gear temp.

On the gear, sounds like the cooler is all that remains. have you checked the oil inlet and outlet temps at the cooler?
 
OK-we bit the bullet and changed port oil cooler with the stbd. oil cooler and vice versa. The problem has now transfered over to the stbd. engine transmission and that is now overheating so we feel that the tranny issue has been solved and it was the oil cooler. It is really weird that in the beginning of this whole process the oil cooler was the first thing we changed with same results. I am guessing that we have multiple issues here. One of the other things we are still seeing is that the engine oil on the port is side at the oil cooler is 20 degrees higher than the stbd. and the intake manifolds on top of engine is 25 degrees hotter than the stbd. This to me does not seem correct, but I wondered if it had to do with counter rotation engine
 
trojan10 said:
One of the other things we are still seeing is that the engine oil on the port is side at the oil cooler is 20 degrees higher than the stbd. and the intake manifolds on top of engine is 25 degrees hotter than the stbd. This to me does not seem correct, but I wondered if it had to do with counter rotation engine
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Is the engine oil hotter than 200 degrees? That is about normal for me, at cruise. I don't see merit in taking the intake manifold temp. There is so much going on there, between the exhaust crossover, to hot water, to the fuel/air charges. Depending on where you see this 25 deg delta, it might be important, and might not.
I suspect that measuring the tranny temp drop thru the oil cooler would have found that issue pretty quickly.
 
diver_dave said:
Is the engine oil hotter than 200 degrees? That is about normal for me, at cruise. I don't see merit in taking the intake manifold temp. There is so much going on there, between the exhaust crossover, to hot water, to the fuel/air charges. Depending on where you see this 25 deg delta, it might be important, and might not.
I suspect that measuring the tranny temp drop thru the oil cooler would have found that issue pretty quickly.
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Yes you are probably right, but I must admit after you put a new oil cooler in when it all first started you tend to put that at the bottom of your list-it does seem weird that a new oil cooler did not solve the issue and it took the change out of the stbd. oil cooler to solve it. I would like to take this opportunity to thank everyone for there input and suggestions which were very helpful in ruling things out and gave us a wealth of knowledge. It was very much appreciated.
 
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