207WF Posted October 23, 2013 Report Share Posted October 23, 2013 Like Ed, I have tried everything on the oil temp issue with no joy, and its been an issue since my '07 was new. I even tried a couple of things not discussed here. Now I am thinking I need an auxilliary oil cooler, mounted separately under the cowl, like we used to do on old VW engines. I wonder if I could get an LOA for that? WF Link to comment Share on other sites More sharing options...
sandpiper Posted October 23, 2013 Report Share Posted October 23, 2013 Like Ed, I have tried everything on the oil temp issue with no joy, and its been an issue since my '07 was new. I even tried a couple of things not discussed here. Now I am thinking I need an auxilliary oil cooler, mounted separately under the cowl, like we used to do on old VW engines. I wonder if I could get an LOA for that? WF Ditto!! Link to comment Share on other sites More sharing options...
Roger Lee Posted October 23, 2013 Report Share Posted October 23, 2013 Of the three here saying they have a high oil temp all the time in climb who has done this? "If the CHT's stay down that means air is moving over the radiator and coolant is flowing normally. If the oil temp is high then something is slowing the oil flow. My money is still on a reduced radius hose. The only way to know for sure is pull off both fire sleeves and watch the hoses as the oil gets hot on the ground with the hoses in their normal state. If you don't just do it like this now you may work at this for ever looking for a cause. this at least needs to be ruled in or out." Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 Of the three here saying they have a high oil temp all the time in climb who has done this? "If the CHT's stay down that means air is moving over the radiator and coolant is flowing normally. If the oil temp is high then something is slowing the oil flow. You may be correct in some cases, but the way you state this it rules out all other possibilities. For instance cool CHT does show flow through the radiator but it doesn't show good air flow through both coolers, that may or may not be true. It doesn't speak to false readings. And it doesn't explain why I was perfectly cool in 2007 and didn't see my 1st high oil temp for 1 1/2 years. Link to comment Share on other sites More sharing options...
Roger Lee Posted October 23, 2013 Report Share Posted October 23, 2013 Hi Ed, Don't shoot the messenger I'm just trying to help solve you problem. If your CHT's (coolant temps are close to this) are cool then air has to move through the coolant radiator. It can not stop and be dead there at the cooler and not flow through the oil cooler too. It would have to pass through both since they are piggy backed for either to work. The fact that you didn't have problems a while back lends more credence for me about a flow issue. Yes it could be a temp probe and switching those as I suggested will rule that in or out. When chasing a ghost problem you should be methodical. You need to take any possible cause and start ruling them out. You should start with the most plausible or common. In this case a reduced radius hose when it gets hot is very common to collapse because it wants to twist or becomes too soft in a turn and this hasn't been ruled in or out yet. We have two highly problematic hoses that can cause this. Sooner or later it will have to be looked at. Might as well look at the most common problem first (remove the fire sleeve on the possible offending hoses) and swap the probes. The probes are very reliable so I don't hold out a lot of hope for that being the problem, but it is possible. I flew yesterday and it was 75F. My temps on a hard 3K vertical climb was only 225F-230F and down to 209F in cruise at 5150 rpm. CHT's were 202F. You have to have a poor probe reading or a slowed oil flow. You have for the most part ruled out air flow issues over the radiator and that shouldn't have changed since a year ago. I would move on to the most common cause first or you may chase this issue for many more months. Diagnostics is all about ruling things in or out and starting with the most common cause. Starting at point "A" then moving to B then C and so on down the logical line. It just makes finding problems faster and easier. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 If you are right that means that my plane developed a reduced radius after 1 1/2 years and then replacing the hoses did not fix it and then at the 5 year change it didn't fix again. We have never removed the fire sleeves and heated it up though. IF FD's routing is a problem and it needs to be changed shouldn't FD get involved? Given how wide spread and long standing this issue is I think they should provide something. Link to comment Share on other sites More sharing options...
Anticept Posted October 23, 2013 Report Share Posted October 23, 2013 CharlieTango, there's a mod where the radiator inlet can be enlarged with a little filing for higher air flow. Dave at FDUSA is probably the best person to ask about recommendations for hot climb outs, but how i solved the problem on hot days is just add 10 kts to Vy. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 Adjusting speed, rate of climb, pitch, flap settings ...etc all have no effect other than I can prevent temps above redline by leveling off and throttling back. The one and only fix is to get to an altitude where OAT is below 70F. Climbing fast gets me there faster. Roger, given the 'fix' in my current condition is to find air at 69F or below how does that speak to the idea of a reduced radius? Link to comment Share on other sites More sharing options...
Roger Lee Posted October 23, 2013 Report Share Posted October 23, 2013 Enlarging the opening to the radiator should only be necessary if the radiator has some blockage and if you can't loosen the radiator mounts and move it more squarely into the air flow opening. I have never had to open up the air flow area. There are others things to do. Reduce radius hose can happen any time. With newly installed hose or older hose. The temps as you say below 69F or above that do make a difference even with a problem. You are still using cooler air at temp. So even with a reduced radius hose that allows higher temps at 70F+ the oil and or all temps will cool better at lower temps after you climb to altitude and of course reduce load on the engine by leveling out. One last thought. The radiator can be adjusted fore and aft some. Make sure it is as far forward and up against the cowl as possible. This makes sure air comes in at the right angle to the radiator's face. Until you check and rule out the hoses everything else will only be a guess and may prolong the issue. Sometimes the shortest problem fix seems to be the most work. Link to comment Share on other sites More sharing options...
Tom Baker Posted October 23, 2013 Report Share Posted October 23, 2013 Roger, wouldn't a reduced radius either starve the engine for oil or create a higher oil pressure depending on where it is at? Link to comment Share on other sites More sharing options...
Roger Lee Posted October 23, 2013 Report Share Posted October 23, 2013 Hi Tom, If the hose was kinked it would be a serious problem. Most issues are only a reduced radius which only slows the oil circulation which allows temps to climb before it gets cooled through the cooler. Reduced radius would not show up in the oil pressure. Sorry Guys, on my way out to do a hose change on an LS. I'll be back tonight. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 Hi Ed, Don't shoot the messenger I'm just trying to help solve you problem. I didn't shoot, Roger. I just pointed out a logical flaw. If the oil temp is high then something is slowing the oil flow. Your saying simply 'If a then b' and that's logically flawed. it goes more like this: If a then b if b then c therefore if a then c I appreciate the help and have for the last 5-6 years on this issue. Over time the fixes change but those of us with this longstanding issue seem to still be chasing a solution. Could a spring be fitted over the oil hose and fire sleeve to prevent reduced radius? Link to comment Share on other sites More sharing options...
sandpiper Posted October 23, 2013 Report Share Posted October 23, 2013 My experiences mirror CT's. Right from the no problem when I got it in 2007, to no change after new hoses. The only thing changed is prop pitch from the factory setting that only allowed 5300 in level WOT to the current 5600. Maybe I should put it back to 5300?? It's gotta be global warming! Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 The 1st time I saw the problem was after a condition inspection done by Tom Dunham. Not blaming Tom but I have never before assoicated the beginning of this condition with a maintenance event. After the inspection I flew to Oregon and couldn't keep under 230F in cruise and couldn't climb in the hot Oregon temps ( it was over 100F ) without getting hot. I really believe that something changed and I don't know what it is. Link to comment Share on other sites More sharing options...
sandpiper Posted October 23, 2013 Report Share Posted October 23, 2013 I am the only one that has ever worked on my plane. I know I haven't done anything to cause this, unless it's prop pitch which I doubt. The only other easy thing I can think of is to adjust the carb to run richer in the summer. So, CT, if one of us finds the cure, it should work on both planes. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 I'm full rich 90% of the time and it keeps my egt down to 1,200. I leveled at 4,000' on Sunday and throttled back and with the needle circuit controlling mixture I went to 1,400 while my oil slowly came down a little. Because of altitude compensation limitations I am too rich most of the time yet I still get hot in climbs. WOT climbs are full rich limited only by the main jet. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 Roger, Jeremy added a 'dedicated ground' to my oil pressure sender and the result is good. I see that ground was dependent on a few connections. How about oil temp? How many connections to ground is it dependent on? If I use my cht gauge to confirm the oil temp gauge any ground issues would negate a confirming result, no? The candy thermometer would take that ground out of the loop. I bring this up because the issue has always been indicated by the gauge and never by smell or other sense of excess temp. Link to comment Share on other sites More sharing options...
Anticept Posted October 23, 2013 Report Share Posted October 23, 2013 Riching the fuel mix will only cool exhaust gases, not the oil temp. If its not an airflow issue, in an older plane, its got to be lead buildup, blocked internal ports, coolant issue, or a blocked or kinked hose issue. Enrichment of fuel lowers chamber temperature, which means that all components will see a reduction in tempterature, but you are correct, there is very little change we would see in the oil from this. CharlieTango, I am going to go with Roger on this one, you might have a hose issue. It's possible to have a malfunctioning temp probe or connection too, but if it's consistent, I am less likely to believe it is a temp probe issue itself. The oil probe uses the ground through the engine. As an additional note, try to only have one ground pathway. If you introduce several ground paths, there is a very tiny chance that stray electrical noise will increase and quite possibly interfere with the probe. Unlikely as this is more common with AC current, but possible. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted October 23, 2013 Report Share Posted October 23, 2013 Anticept, The thing is my oil temp readings are readings of resistance to ground and the grounding on a CTSW is sub-standard (for aviation), I do need to rule out that my issue isn't a grounding issue. A redundant path to ground isn't ideal but 'I'll go with Roger on this' its his fix. Link to comment Share on other sites More sharing options...
Anticept Posted October 23, 2013 Report Share Posted October 23, 2013 Anticept, The thing is my oil temp readings are readings of resistance to ground and the grounding on a CTSW is sub-standard (for aviation), I do need to rule out that my issue isn't a grounding issue. A redundant path to ground isn't ideal but 'I'll go with Roger on this' its his fix. Just replace the existing ground with bigger wire and better connectors, reroute, or combination, once you figure out if the ground is the problem. Also, what gauge do you have? Link to comment Share on other sites More sharing options...
Roger Lee Posted October 24, 2013 Report Share Posted October 24, 2013 Hi Ed, Long day here playing with an LS's hoses. Loads of fun. Just happy to be off my feet. So lets talk about this oil temp. Changing the carb to be richer really won't help the oil temps.You could put a dedicated ground wire set up like I have posted in the maint. section and it will take care of just about all your grounding issues. Could this be your problem not very likely because there are other instruments that are far more sensitive to poor grounds and those aren't acting up. If it were my plane I would check both those oil hoses I told you about. The other thing I thought of this morning is a piece of debris could have come through the hose and become lodged in the oil cooler. The cooler can be removed and flushed with lacquer thinner and then blown out with air to clean and purge it. Make the first purge with the air in reverse flow from the oil. All these things need to be done to rule them in or out. I truly believe this is a flow issue that slows the oil return which cause extra heat in the oil. The LS I worked on today has a reduced radius hose coming out the bottom of the engine and returns back to the tank. I rerouted the "S" turns that FD put in and brought the hose straight out to the left under cyl. #2 & #4 and put a 90 degree fitting on the hose instead of a straight fitting that goes back into the tank. This hose now has a really nice gentle sweep for a turn and has full flow. Link to comment Share on other sites More sharing options...
sandpiper Posted October 24, 2013 Report Share Posted October 24, 2013 Went for a sunset cruise this evening. Field elevation 180', climbed to 2500 MSL at 85K then set up for a 5200 cruise. OAT at altitude was 67F. When it all settled down, CHT was 195, oil temp 215. Seems high for 67F. Reduced power to 5000 and oil temp settled at 210F with CHT at 190. Roger, I did the same hose off the bottom of the engine reroute that you indicate above last Nov. Link to comment Share on other sites More sharing options...
Roger Lee Posted October 24, 2013 Report Share Posted October 24, 2013 Hi John, Your temp looks in the normal range to me. Link to comment Share on other sites More sharing options...
Jim Meade Posted October 24, 2013 Report Share Posted October 24, 2013 If oil temp goes up, often oil pressure will go down. Worth a look, anyway, to see if there is any correlation. If not, might be an instrument issue. BTW, for the inexperienced lurkers, one does not increase Vy by 10 knots (lower the nose in climb). Vy is defined by FAR 1.2 as "VY means speed for best rate of climb," so it is not a rate one changes. One can elect to use a cruise climb or other user defined speed which results in lowering the nose, getting better airflow over the radiator and usually increasing engine cooling. Link to comment Share on other sites More sharing options...
Anticept Posted October 24, 2013 Report Share Posted October 24, 2013 BTW, for the inexperienced lurkers, one does not increase Vy by 10 knots (lower the nose in climb). Vy is defined by FAR 1.2 as "VY means speed for best rate of climb," so it is not a rate one changes. Details details, you know what I mean Link to comment Share on other sites More sharing options...
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