Major Cooling System issues, Flap system removed by PO Options

[Gatornapper]

Need the Brain Trust help again - big time.

Up to now, nothing I've faced in getting this sweet 14 running and back on the road has been major or disheartening. Lots of new stuff, running pretty good but not perfect, etc. That just changed.

Ever since getting the engine running a few months ago, I was concerned that it took a long time to warm up. My first 1 hour + drive was last week - and temps got too high for my comfort - about 1/4" from red line. So I've been drilling down on that issue.

For one thing, car sat in a barn (new one) for 12 years - so I wondered about mice nests above the cylinders from the day I bought the car. Yesterday with my scope I found, yes, they are there between the cylinders - at least between 2 & 4. I think I can get them out with a small vacuum through the spark plug holes in the top tins.....we'll see.

Due to total ignorance of 914's and VW engines, I know nothing of the air ducting system, but in the learning process, and thanks to anderssj , I find the whole flap/door system and its controls are missing. Gone.

So I can only assume that the PO removed them due to problems with overheating. Stupid move for sure. I have to correct that. I understand that move itself could cause overheating.

I dread pulling the carbs, intake manifolds, distributor and other stuff to get the top tins off.

Plan is to see if I can get the mouse stuff off the cylinders with a small vacuum, make sure all is clean with my scope. If successful, I'll then drive the car and see if it still gets too hot. If I can't get the debris removed with vacuum, I know I have to pull the top tins.

But I am told that not having the flap system itself could cause overheating. So I have to get that system installed and working.

Yes, I know the many potential causes of overheating like improper timing, plugs, etc. Timing good, plugs good - new. Valves adjusted by dealer about 1,500 miles ago.

Got a lot of work ahead - all when I wanted to have the car ready for the big PCA 9/14 914 Vintage Drive.

Any help and advice is of course, as always, appreciated.

GN

[ChrisFoley]

No, I have the engine out of the car. I wouldn't attempt what I am doing with the engine installed.
I thought I could get the shroud out of the way without pulling the cylinder tin off first. However a previous owner riveted the flap in place while the top tin was off. There's no driver side flap since it's attached to the missing crossbar.
Once I got the right cylinder tin out of the way everything went smoothly.

I'm not re-installing any stock parts. I'm modifying the oil cooling system by replacing the factory oil cooler with my custom made thermostat that has ports for a remote cooler. The cooler is mounted below the rear trunk and has a fan to pull air up through the cooler. A block-off plate replaces the flap on the passenger side so no air can escape from where the stock cooler used to be.

I think oil temps of 250 are not uncommon for a stock 2L being driven hard. I would prefer to see it peak no higher than 225.

[Gatornapper]

Chris -

Thank you. I've never seen your oil cooler idea, only the front cooler ones. But I have wondered myself why a rear mounted cooler with a fan could not be used. Sounds like a great design, especially since you aren't adding your cooler to the stock one but replacing it.

I'd love to hear your reasons for not using both - I'm sure they are solid and sound.

Have you patented your design? I'd love to do the same on mine - but you are way to far from me to do my work.

Agree on the oil temp.....you confirmed my thoughts on the stock design......

Glad I'm running synthetic.....have been on all my vehicles since 1977....never an engine failure since then, and we drive all out vehicles until they are worth almost nothing....and die of other major mechanical issues.

GN

No, I have the engine out of the car. I wouldn't attempt what I am doing with the engine installed.

I thought I could get the shroud out of the way without pulling the cylinder tin off first. However a previous owner riveted the flap in place while the top tin was off. There's no driver side flap since it's attached to the missing crossbar.
Once I got the right cylinder tin out of the way everything went smoothly.

I'm not re-installing any stock parts. I'm modifying the oil cooling system by replacing the factory oil cooler with my custom made thermostat that has ports for a remote cooler. The cooler is mounted below the rear trunk and has a fan to pull air up through the cooler. A block-off plate replaces the flap on the passenger side so no air can escape from where the stock cooler used to be.

I think oil temps of 250 are not uncommon for a stock 2L being driven hard. I would prefer to see it peak no higher than 225.

[ChrisFoley]

Chris -

Thank you. I've never seen your oil cooler idea, only the front cooler ones. But I have wondered myself why a rear mounted cooler with a fan could not be used. Sounds like a great design, especially since you aren't adding your cooler to the stock one but replacing it.

I'd love to hear your reasons for not using both - I'm sure they are solid and sound.

Have you patented your design? I'd love to do the same on mine - but you are way to far from me to do my work.

Agree on the oil temp.....you confirmed my thoughts on the stock design......

Glad I'm running synthetic.....have been on all my vehicles since 1977....never an engine failure since then, and we drive all out vehicles until they are worth almost nothing....and die of other major mechanical issues.

GN

I think the stock cooler is terribly inefficient where it is right up against the block essentially, and the stock oil circuitry has oil flow thru the cooler based on pressure not temperature. High oil pressure = no oil moving in the cooler.

Nothing patentable in my design, just good use of available components combined with some custom made parts to complete the assembly. The most significant of the custom made parts is the oil thermostat which mounts on the engine where the cooler used to be. That ensures the oil cooler has little to no flow until the oil is 180F.
My goal with the kit is to create something that works well and most any shade tree mechanic can install. I'm just learning about the complexities of installing this in a car with stock heat exchangers right now. My early efforts were aimed at modified engines running race headers.

Be careful with synthetic oil. A high ZDDP content is essential for minimizing lifter/cam wear.

[Gatornapper]

Thanks, Chris.

"Be careful with synthetic oil. A high ZDDP content is essential for minimizing lifter/cam wear."

And here I've preached this to owners of old Triumph (and other makes) motorcycles for years - but had not applied it to the '76 VW engine. Of course!

Back to the Brad Penn I run in my old Triumph's........partial synthetic......plenty of ZDDP....

"High oil pressure = no oil moving in the cooler..." TOTALLY do not understand this one - the higher the pressure, the more the oil should flow in volume!

Does your system have a fail-safe mode if your thermostat regulating the flow fails?

Thank,

GN

Chris -

Thank you. I've never seen your oil cooler idea, only the front cooler ones. But I have wondered myself why a rear mounted cooler with a fan could not be used. Sounds like a great design, especially since you aren't adding your cooler to the stock one but replacing it.

I'd love to hear your reasons for not using both - I'm sure they are solid and sound.

Have you patented your design? I'd love to do the same on mine - but you are way to far from me to do my work.

Agree on the oil temp.....you confirmed my thoughts on the stock design......

Glad I'm running synthetic.....have been on all my vehicles since 1977....never an engine failure since then, and we drive all out vehicles until they are worth almost nothing....and die of other major mechanical issues.

GN

I think the stock cooler is terribly inefficient where it is right up against the block essentially, and the stock oil circuitry has oil flow thru the cooler based on pressure not temperature. High oil pressure = no oil moving in the cooler.

Nothing patentable in my design, just good use of available components combined with some custom made parts to complete the assembly. The most significant of the custom made parts is the oil thermostat which mounts on the engine where the cooler used to be. That ensures the oil cooler has little to no flow until the oil is 180F.
My goal with the kit is to create something that works well and most any shade tree mechanic can install. I'm just learning about the complexities of installing this in a car with stock heat exchangers right now. My early efforts were aimed at modified engines running race headers.

Be careful with synthetic oil. A high ZDDP content is essential for minimizing lifter/cam wear.

[ChrisFoley]

...

"High oil pressure = no oil moving in the cooler..." TOTALLY do not understand this one - the higher the pressure, the more the oil should flow in volume!

Does your system have a fail-safe mode if your thermostat regulating the flow fails?

The stock pressure relief valve in a Type 4 engine also incorporates a cooler bypass circuit.
When pressure is high most of the oil goes around the cooler, not through it.
Its essentially a thermostat to help with warm up, but also allows very high oil temperatures during hard driving. I make a pressure valve insert which defeats the bypass, forcing the oil thru the cooler at all times.

My thermostat is internally identical to the remote thermostats that are commonly used in external cooler plumbing. There is no fail-safe. These thermostats use oil temperature, not pressure, to open the valve. When the oil is hot it all goes thru the cooler.

[Gatornapper]

Cool! Great design...

[/quote]
The stock pressure relief valve in a Type 4 engine also incorporates a cooler bypass circuit.
When pressure is high most of the oil goes around the cooler, not through it.
Its essentially a thermostat to help with warm up, but also allows very high oil temperatures during hard driving. I make a pressure valve insert which defeats the bypass, forcing the oil thru the cooler at all times.

My thermostat is internally identical to the remote thermostats that are commonly used in external cooler plumbing. There is no fail-safe. These thermostats use oil temperature, not pressure, to open the valve. When the oil is hot it all goes thru the cooler.
[/quote]