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Optimusglen
I'm in the process of installing my 6 and have come to the oil lines. My entire setup is planned as AN-12, and I see options for AN12 one-way check valves from a number of retailers.

One example: https://www.jegs.com/i/JEGS/555/150024/1000...KEaAnyVEALw_wcB

I have seen the threads on here and on Pelican about the Rothsport valve, but the price and the lack of AN fittings have drawn me away from it.

Is there some other reason that someone should fork out 300 for the Rothsport unit?
Mark Henry
QUOTE(Optimusglen @ Jul 24 2021, 11:16 AM) *


Is there some other reason that someone should fork out 300 for the Rothsport unit?


Because it's a very expensive engine and the Rothsport check valve mechanism is a direct copy of the factory Porsche GT3 check valve.

I looked at the link and the 5 psi opening concerns me. The GT3 valve is designed to open by suction, not pressure.

Too bad you are doing this now, I have a 914 coming over the winter for the exact same mod and other repairs. It's all AN fittings and hose and the chap has a late 911 "S hose" rothsport valve. I will likely be doing it similar to my install, using custom made adapters and a modified (cut down) 911 S hose.
Optimusglen
QUOTE(Mark Henry @ Jul 24 2021, 10:32 AM) *

QUOTE(Optimusglen @ Jul 24 2021, 11:16 AM) *


Is there some other reason that someone should fork out 300 for the Rothsport unit?


Because it's a very expensive engine and the Rothsport check valve mechanism is a direct copy of the factory Porsche GT3 check valve.

I looked at the link and the 5 psi opening concerns me. The GT3 valve is designed to open by suction, not pressure.

Too bad you are doing this now, I have a 914 coming over the winter for the exact same mod and other repairs. It's all AN fittings and hose and the chap has a late 911 "S hose" rothsport valve. I will likely be doing it similar to my install, using custom made adapters and a modified (cut down) 911 S hose.


Very good point on the sucttion vs pressure.
Retroracer
Glen - humbly suggest that you COULD hold off for now on fitting the valve - recall they were not fitted from the factory, and your engine build looks pretty stock 2.2T - plus, its a relatively easy item to retrofit if problems occur.

I get that you want to get the AN-12 lines and fitttings done once and done correctly; just saying it might be an unnecessary addition....

- Tony

Optimusglen
Also a good point, I had my oil pump rebuilt by Henry at Supertech as well.

I plan on doing that line in 2 sections still, to aide in oil changes I'll probably do a T there with a cap. Maybe if/when I have issues I'll just replace that one section and deal with it all then.
mlindner
I'm with Mark Henry. I also installed a Rothport two month ago, tank would drain into sump in less than a week. Best, Mark
Mark Henry
I agree I would wait to see if you have this issue, I'm guessing but it seems only 1 or 2 in 10 have this issue.
And I agree you need a T fitting with a drain that will be before the check valve. It makes it much easier to change the oil, but it will also help out if you need to install the valve in the future.
JmuRiz
Good to know, I’ll do the same when my engine gets in.
fixer34
QUOTE(mlindner @ Jul 24 2021, 12:11 PM) *

I'm with Mark Henry. I also installed a Rothport two month ago, tank would drain into sump in less than a week. Best, Mark

Search the threads on here, I did this on my factory -6 a year or so ago. Posted several pictures. Mine has factory oil lines and heat exchangers; it gets a little tight in there. Be very careful when looking at 'check valves', the Rothsport is not like the conventional check valve you would buy for a sump pump.
Yes it's expensive, what isn't on a six? But it works as advertised. I had to keep a turkey pan under mine before installing it. Six months of sitting and I would have 3-4 quarts of oil in the pan (still not sure where it was leaking from the engine).
Six months of sitting now and I might have 3-4 tablespoons of oil.
porschetub
QUOTE(fixer34 @ Jul 26 2021, 05:32 AM) *

QUOTE(mlindner @ Jul 24 2021, 12:11 PM) *

I'm with Mark Henry. I also installed a Rothport two month ago, tank would drain into sump in less than a week. Best, Mark

Search the threads on here, I did this on my factory -6 a year or so ago. Posted several pictures. Mine has factory oil lines and heat exchangers; it gets a little tight in there. Be very careful when looking at 'check valves', the Rothsport is not like the conventional check valve you would buy for a sump pump.
Yes it's expensive, what isn't on a six? But it works as advertised. I had to keep a turkey pan under mine before installing it. Six months of sitting and I would have 3-4 quarts of oil in the pan (still not sure where it was leaking from the engine).
Six months of sitting now and I might have 3-4 tablespoons of oil.


Glen has the same engine as mine and with his upgraded pump it should be less of an issue...it won't stop drain back but if the pump is up to spec the oil is quickly be scavenged back to the oil tank from the engine case ,I don't see an issue.
Seems its more of an problem with the larger capacity motors but not real sure on that.
mepstein
I would get it if you need it but don’t assume you will.
mb911
It's interesting how each engine is different. Mine does not need it but the engine is fairly fresh.
jd74914
Not a /6 guy, so giving my unsolicited opinion here, but as someone who has spent my entire adult life designing fluid systems, there is no way I would ever put a check valve (or anything really) between the tank and pump inlet. I know people say this is 100% failure proof, but in my experience that just means no one has had a failure yet. While smoking on startup isn't too cool, oil starving an engine is worse.
mepstein
QUOTE(jd74914 @ Jul 26 2021, 11:36 AM) *

Not a /6 guy, so giving my unsolicited opinion here, but as someone who has spent my entire adult life designing fluid systems, there is no way I would ever put a check valve (or anything really) between the tank and pump inlet. I know people say this is 100% failure proof, but in my experience that just means no one has had a failure yet. While smoking on startup isn't too cool, oil starving an engine is worse.

The Porsche engineers disagree with you. They use it on the GT3 and Rothsport is no slouch when it comes to Porsche engine building.
jd74914
QUOTE(mepstein @ Jul 26 2021, 10:40 AM) *

The Porsche engineers disagree with you. They use it on the GT3 and Rothsport is no slouch when it comes to Porsche engine building.

I knew someone would take issue with that statement. All you need to know is any decent FMEA will have 'check valve failed closed' on it. You can't get around that, though you can debate the severity and occurrence rates.

I don't know that you can say the Porsche engineers disagreed with the premise-we don't know what their requirements were. A requirements driver may have been that people who spend $200k on a GT3 don't want to see smoke on startup, or that can't be risked from for emissions compliance, who knows. So with say 2000 GT3s produced, and a 99.9% valve reliability rate means maybe 2 [potentially] damaged engines. Not so bad on from warrantee cost perspective. They may even have engine control logic to prevent revving from idle with loss of oil pressure at some time duration from startup which is when you see 99% of check valve issues.

All situations different from what you see in the aftermarket.
PanelBilly
I’m not using one either. Maybe there’s a little smoke after it’s been sitting for a few weeks but nothing that I’ve been alarmed about. I guess if I start seeing a problem, I’ll know what else I can add to the car
ClayPerrine
QUOTE(jd74914 @ Jul 26 2021, 10:36 AM) *

Not a /6 guy, so giving my unsolicited opinion here, but as someone who has spent my entire adult life designing fluid systems, there is no way I would ever put a check valve (or anything really) between the tank and pump inlet. I know people say this is 100% failure proof, but in my experience that just means no one has had a failure yet. While smoking on startup isn't too cool, oil starving an engine is worse.



I tried the check valve on the 4.0. Never could get oil pressure. Gutted the valve, and the oil pressure was back. I verified it was not installed backwards.

I may be a minority here, but it didn't work for me. Rothsport was very helpful in trying to diagnose it, but in the end I decided the smoking at startup after sitting a while was a small price to pay to insure it was getting oil pressure.

I did not ask for a refund from Rothsport. They are an honest parts vendor, and they believe in their product. I would buy from them again, just not one of the check valves.

Clay
mb911
QUOTE(ClayPerrine @ Jul 26 2021, 09:29 AM) *

QUOTE(jd74914 @ Jul 26 2021, 10:36 AM) *

Not a /6 guy, so giving my unsolicited opinion here, but as someone who has spent my entire adult life designing fluid systems, there is no way I would ever put a check valve (or anything really) between the tank and pump inlet. I know people say this is 100% failure proof, but in my experience that just means no one has had a failure yet. While smoking on startup isn't too cool, oil starving an engine is worse.



I tried the check valve on the 4.0. Never could get oil pressure. Gutted the valve, and the oil pressure was back. I verified it was not installed backwards.

I may be a minority here, but it didn't work for me. Rothsport was very helpful in trying to diagnose it, but in the end I decided the smoking at startup after sitting a while was a small price to pay to insure it was getting oil pressure.

I did not ask for a refund from Rothsport. They are an honest parts vendor, and they believe in their product. I would buy from them again, just not one of the check valves.

Clay



That is a very good reason for me to live with it should I ever get a bit of drain into the case.
9146C
When I was completing my "rustoration" project and re-installing my 2.7L, I was debating installing one of these (Rothsport) check valves.

My motor had less than 10,000 miles when it was re-installed in my finished project.

I had only ever had one instance of "smoke" (no external oil leaks) in the time I've had the motor installed (prior to rebuilding my car) and opted not to proceed with the check valve. I have not had any issues in the last 3-4 months that I've again begun driving the car.

When I was researching the Rothsport valve, I recall reading a comment somewhere that it is better to have a "prime" on the pump when the motor is started from cold...sounds logical...is it true? Who knows? The argument went further to say that a check valve would (or could) prevent the pump from having this initial prime, and may, in theory prolong low/no oil pressure immediately following engine start-up. Again, it is likely a theory with little or no merit. I did not find any data to support the claim either way.

In my simple way of thinking, an oil accumulation in the engine case (during shutdown, prolonged non-use) is the result of the (excessive) clearance of the oil pump bleeding through. Yes, oil viscosity, ambient temperatures, etc all play a factor. In my case, my oil pump was brand new when I rebuilt the motor so I don't expect to have any issues (with start-up blue) for a long time to come. That sentence is not meant to say/imply that a used pump cannot be rebuilt to factory tolerances.

I may be way off base with my assumptions and observations, but, I'm in the camp of others here with try it if you need it. IMHO, the check valve is merely a "band-aid" for an oil pump that is (beginning) showing signs of wear.
fixer34
QUOTE(9146C @ Jul 26 2021, 01:05 PM) *

When I was completing my "rustoration" project and re-installing my 2.7L, I was debating installing one of these (Rothsport) check valves.

My motor had less than 10,000 miles when it was re-installed in my finished project.

I had only ever had one instance of "smoke" (no external oil leaks) in the time I've had the motor installed (prior to rebuilding my car) and opted not to proceed with the check valve. I have not had any issues in the last 3-4 months that I've again begun driving the car.

When I was researching the Rothsport valve, I recall reading a comment somewhere that it is better to have a "prime" on the pump when the motor is started from cold...sounds logical...is it true? Who knows? The argument went further to say that a check valve would (or could) prevent the pump from having this initial prime, and may, in theory prolong low/no oil pressure immediately following engine start-up. Again, it is likely a theory with little or no merit. I did not find any data to support the claim either way.

In my simple way of thinking, an oil accumulation in the engine case (during shutdown, prolonged non-use) is the result of the (excessive) clearance of the oil pump bleeding through. Yes, oil viscosity, ambient temperatures, etc all play a factor. In my case, my oil pump was brand new when I rebuilt the motor so I don't expect to have any issues (with start-up blue) for a long time to come. That sentence is not meant to say/imply that a used pump cannot be rebuilt to factory tolerances.

I may be way off base with my assumptions and observations, but, I'm in the camp of others here with try it if you need it. IMHO, the check valve is merely a "band-aid" for an oil pump that is (beginning) showing signs of wear.


I'm guessing I have plenty of clearances; 120k on the motor and as far as I know the case has never been split. Car sits a good part of the time, especially winter months. Got tired of cleaning up the leaking oil. My choice was a Rothsport valve, some new hose,(about $400 total) and vexatious work over a couple months time. OR a complete engine rebuild to the tune of $15k+ and about a year of waiting.

Spun the engine for a few minutes with coil disconnected, started to build a little pressure. reconnected, started it up and pressure went to 50psi right away. I keep an eye on the gauge while driving (have a small aftermarket one) and it's been fine so far. And no oil leaks to speak of.
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