Lifter noise solutions needed - (gasket improperly installed)
03-07-2012, 11:04 PM
#61
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With the oil cooler outlet blocked you are relying totally on the bypass valve, which is very rarely activated if at all in the presence of an oil cooler. Who knows if it is opening adequately. An oil pressure reading of 3.5 bar hot idle, which is higher than usual, could actually indicate that the bypass may be inadequate, raising the pressure in the blocked passage where the oil pressure sender is.
I didn't know Brian is running with no oil cooler. Why would you do that? All model year radiators have oil coolers built in. I didn't know there are some years running without oil coolers. Looking at the Service Info Tek books for 78 and 79, they show cooler paths in the oil flow diagrams with the thermostat and all. What years have the cooler plugged off?
You should remove the cap on the bypass and take out the valve if you are running with the oil cooler passage blocked.
I didn't know Brian is running with no oil cooler. Why would you do that? All model year radiators have oil coolers built in. I didn't know there are some years running without oil coolers. Looking at the Service Info Tek books for 78 and 79, they show cooler paths in the oil flow diagrams with the thermostat and all. What years have the cooler plugged off?
You should remove the cap on the bypass and take out the valve if you are running with the oil cooler passage blocked.
03-07-2012, 11:39 PM
#62
Looking at this oil flow diagram....there shouldn't be an issue if he plugged the oil cooler lines and removed the innards of the oil thermostat..since oil will flow through and up and out of the thermostat area to the filter.
If he left the thermostat innards there...then he could conceivably have an issue as it is trying to divert oil to the cooler lines....but the "bypass" should open with the pressure differential, and the oil will bypass the cooler circuit and go right to the filter.
Does the 83/84 4.7 liter engine have both the high pressure bypass (#3) and the differential bypass (#4)?... my 91 block only has the high pressure bypass (I think they removed the differential pressure bypass since the external oil cooler leaking would be obvious...as opposed to the internal one...filling the coolant system)...
If he left the thermostat innards there...then he could conceivably have an issue as it is trying to divert oil to the cooler lines....but the "bypass" should open with the pressure differential, and the oil will bypass the cooler circuit and go right to the filter.
Does the 83/84 4.7 liter engine have both the high pressure bypass (#3) and the differential bypass (#4)?... my 91 block only has the high pressure bypass (I think they removed the differential pressure bypass since the external oil cooler leaking would be obvious...as opposed to the internal one...filling the coolant system)...
Most of the parts shown in PET in the area of the oil cooler ports are omitted in cars without an oil cooler. If an engine that was originally assembled to be used with an oil cooler has the oil cooler disconnected and the ports capped, with no other parts being removed, you will have a problem. The system does have an over pressure bypass, to deal with a blocked cooler presumably so you will get some pressure, but the drop is significant. Also, I think the reason your noise gets worse once the engine warms up could be because the oil cooler is bypassed until the engine is warm in a normally operating car. So maybe things get even worse once the system tries to switch in the "plugged" (non-existent) oil cooler.
Last edited by Tom. M; 12-14-2012 at 05:12 PM.
03-07-2012, 11:45 PM
#63
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The 83-84 US cars do not have a built in oil cooler in the radiator.
In addition to the extra bypass, there is also a thermally operated valve. Both are omitted on cars with no oil cooler.
In addition to the extra bypass, there is also a thermally operated valve. Both are omitted on cars with no oil cooler.
03-07-2012, 11:55 PM
#65
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Oh, so he removed the thermostatic valve? OK. Nevermind.
Eric - thanks for clarifying about 83/4. News to me. There's no indication in the service info for those years. I see PET shows "radiator with oil cooler" and another just called "radiator". Interesting.
Eric - thanks for clarifying about 83/4. News to me. There's no indication in the service info for those years. I see PET shows "radiator with oil cooler" and another just called "radiator". Interesting.
03-08-2012, 12:29 AM
#66
Isn't there also something about one of those springs that are at that area for the oil cooler connections controlling at what point the oil pressure is bypassed? A stronger spring creates more total oil pressure?
03-08-2012, 01:40 AM
#67
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03-08-2012, 01:49 AM
#68
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I'm the last guy to take any offense when it comes to someone mentioning whether or not I forgot to check or do something while working on one of these cars, anything is possible in my book.
So I do appreciate your persistence Greg, much better than not getting involved at all and taking the postion that "he'll figure it out sooner or later, for better or for worse".
So that being said, the only thing I can think of that would affect oil control in the motor is that this is an '83 4.7L motor which would normally have the external oil cooler.
Brian had mentioned that he doesn't run the external cooler on his 4.7L in the Estate, and just runs the 4.5L plugs in place of where the oil cooler lines would go to the block.
When I look at the PET, it appears to show all of the same internal workings in the oil pressure regulator with both motors, however the PET does also show the '79 motor with the oil cooler lines which it doesn't have. But, based on the PET, I presumed that both motors had the same parts to the oil pressure regulator.
If the internals are not the same, and capping the oil cooler line ports without doing anything further is causing an oil starvation problem, then yes, " Houston, we may have a problem. "
Could this be the issue?
So I do appreciate your persistence Greg, much better than not getting involved at all and taking the postion that "he'll figure it out sooner or later, for better or for worse".
So that being said, the only thing I can think of that would affect oil control in the motor is that this is an '83 4.7L motor which would normally have the external oil cooler.
Brian had mentioned that he doesn't run the external cooler on his 4.7L in the Estate, and just runs the 4.5L plugs in place of where the oil cooler lines would go to the block.
When I look at the PET, it appears to show all of the same internal workings in the oil pressure regulator with both motors, however the PET does also show the '79 motor with the oil cooler lines which it doesn't have. But, based on the PET, I presumed that both motors had the same parts to the oil pressure regulator.
If the internals are not the same, and capping the oil cooler line ports without doing anything further is causing an oil starvation problem, then yes, " Houston, we may have a problem. "
Could this be the issue?
Everyone learns from stuff like this. It's good for the community. And as hard as it might be to believe, I'm not a "money first" kind of guy, but love these cars and want to help them continue on.
Hopefully, it's just a "stuck" lifter or two, but it's sometimes better to brainstorm this stuff....and there's a really great group of super smart people helping here.
Those guys are already answering your questions about plugging the oil cooler ports, complete with drawings.
03-08-2012, 03:13 AM
#69
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Nope, I didn't.
1) I didn't think that when the thermostatic valve actuated that it resulted in a 100% diversion to the cooler. It's suprising to me that Porsche would design it this way, with all the eggs in the one basket and not leaving some oil in the motor.
2) I also thought by actually removing the thermostatic valve, the result would be a pressure drop in the system.
So this is news to me Eric. I presumed that my 4.7L motor used a radiator cooler because when I got it , the oil cooler ports weren't capped off like on the 4.5L. So are you saying that the 4.7L and 4.5L motor are identical (like what the PET shows?) and that I don't need to remove the thermostatic valve?
1) I didn't think that when the thermostatic valve actuated that it resulted in a 100% diversion to the cooler. It's suprising to me that Porsche would design it this way, with all the eggs in the one basket and not leaving some oil in the motor.
2) I also thought by actually removing the thermostatic valve, the result would be a pressure drop in the system.
So this is news to me Eric. I presumed that my 4.7L motor used a radiator cooler because when I got it , the oil cooler ports weren't capped off like on the 4.5L. So are you saying that the 4.7L and 4.5L motor are identical (like what the PET shows?) and that I don't need to remove the thermostatic valve?
03-08-2012, 04:46 AM
#70
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Would a simple solution to this "is she or isn't she" dilemma be to use one oil cooler connecting pipes in place of the plugs - connect both ports in a loop and see if it makes a difference ?
03-08-2012, 05:07 AM
#71
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When the cooler hoses on the 78 started to leak I put in plugs from an 80 motor with no adverse effects other than curing the oil leak.
03-08-2012, 09:05 AM
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If you have no oil cooler you do need to remove the thermostatic valve. With the thermostic valve in place once the oil warms up the thermostatic valve will close and route all oil to the cooler. The only path for the oil then is via the over-pressure relief, which is probably why you see such a high hot idle pressure. The fact that you received your 4.7 motor with the oil ports not capped strongly suggests that it was used previously with an oil cooler (Euro 4.7s had a cooler US did not). If it was previously used with an oil cooler then parts need to be removed as well as capping the ports.
Jon: If you take things apart far enough to to connect a hose between the ports you might as well just see what is installed. There is no question that the thermostatic valve should not be present if no oil cooler is used. Also, it sounds like he has no cooler, and likely no oil cooler lines to play with anyway.
Dan: You have stated in earlier threads that you just blocked your ports, without removing any other parts. In those earlier threads it was stated (by others) that this was INCORRECT. I am also sure that it is INCORRECT to do so. Spreading this INCORRECT advice is dangerous. You may be getting away with it because your over pressure bypass spring is weak or maybe you just don't push the car very hard. Regardless your car is suffering from lower oil pressure than it otherwise could have.
If someone else doesn't beat me to it, when I get home from work this afternoon I'll list just which (few) parts should be installed in this area. There are parts shown in PET that go in the blocked ports, as well as parts that go in above the oil pressure sender. Very few of the these parts are supposed to be installed in cars with no oil cooler.
Jon: If you take things apart far enough to to connect a hose between the ports you might as well just see what is installed. There is no question that the thermostatic valve should not be present if no oil cooler is used. Also, it sounds like he has no cooler, and likely no oil cooler lines to play with anyway.
Dan: You have stated in earlier threads that you just blocked your ports, without removing any other parts. In those earlier threads it was stated (by others) that this was INCORRECT. I am also sure that it is INCORRECT to do so. Spreading this INCORRECT advice is dangerous. You may be getting away with it because your over pressure bypass spring is weak or maybe you just don't push the car very hard. Regardless your car is suffering from lower oil pressure than it otherwise could have.
If someone else doesn't beat me to it, when I get home from work this afternoon I'll list just which (few) parts should be installed in this area. There are parts shown in PET that go in the blocked ports, as well as parts that go in above the oil pressure sender. Very few of the these parts are supposed to be installed in cars with no oil cooler.
03-08-2012, 09:53 AM
#73
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When my 79 suffered a failed radiator and still under warranty, the dealer installed a non-cooler radiator and blocked off the connections.
03-08-2012, 10:24 AM
#74
Again, looking at the diagram, if the thermostat assembly is still in there, the bypass should allow the oil to get to where it needs to go. But...get the gut's out of there and see if the lifter noise goes away.
03-08-2012, 11:37 AM
#75
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Interesting thread.....my thoughts
after listening to the engine STOP STOP STOP...DO NOT RUN IT AGAIN.....ask me how I know....when the engine that came in the Estate blew up
It sounded ALOT like yours.....we didn't have a working oil pressure gauge at that race...so I can't comment on pressure
I do NOT run an oil cooler.....I tapped the plugs and that is where I measure oil pressure and temp...given my low HP I don't think its needed, but couldn't hurt either....the radiator in the car has both cooler fittings
Something clearly is VERY wrong....but all you did was change the cams-cam boxes right?
after listening to the engine STOP STOP STOP...DO NOT RUN IT AGAIN.....ask me how I know....when the engine that came in the Estate blew up
It sounded ALOT like yours.....we didn't have a working oil pressure gauge at that race...so I can't comment on pressure
I do NOT run an oil cooler.....I tapped the plugs and that is where I measure oil pressure and temp...given my low HP I don't think its needed, but couldn't hurt either....the radiator in the car has both cooler fittings
Something clearly is VERY wrong....but all you did was change the cams-cam boxes right?