The external cooler has a Mocal sandwich adapter between the oil filter. There is no thermostat in the sandwich adapter. So oil is flowing through the cooler hot or cold. There is an inline switch that turns on the fan when the oil reaches 180*. I will disconnect the oil cooler and take it for a drive, as I'll try anything at this point to avoid tearing down the engine. Not dropping the engine until I talk to my machinist on Monday.

Ahh. Yes, there would always be oil to the filter.

Disconnected the Oil cooler and removed the sandwich adapter. My mistake, the Mocal adapter does have a thermostat. I put everything back together minus the sandwich plate. It is going to be raining all weekend here in NJ, so I will have to wait until Monday to take it for a test drive and get it up to temp. Wish me luck!

Following this thread with interest. Like @VaccaRabite asked, I'm running the 150psi two pole sender that is turning on my dash light when the engine is hot. It's hard to tell when looking at a 0-150 psi gauge if it's 8 or 0 psi, though. I up'd my idle to prevent the problem [for now] but as I sit here and wait for my back ordered single pole 80 psi sender, I worry that my "hot" oil pressure might be an issue. Trying to remain calm

I'll run the car today see how my numbers compare with @Geezer914 .

What is you oil pressure at 3000 rpm? The dual pole sender I had on my 80lb. electric gauge made the green light come on at idle unless it was above 1200 rpm. With the single pole sender my gauge reads 7 lbs hot idle and no green light.

Well, I forced myself to take the 914 through the central Texas Hill Country to test my oil pressure. Nothing but beautiful weather after a few rainy days.

Engines certainly differ between builds. Here are my pressure readings:

Cold:
60-65lbs at startup/cold idle at 800-900 rpms

Hot:
30-35lbs @3000rpms
7-10lbs at 1000-1100 rpms Note: Hard to tell on my 0 - 150lb gauge

In the past, if I dropped the engine rpms to around 700-900rmps when hot, my pressure light would flicker on.

Setup:
2375 engine - dual Weber 44 IDFs
Low Pressure Relief = Tangerines Oil Pressure Relief Valve
High Pressure Relief = European motor works slug with original piston
26mm Schadek Oil pump (not modified)
No external oil cooler
15w-50 oil
150lb VDO dual-pole sender/gauge

Click to view attachment

And what is wrong with this picture? I bet she runs nice

Wouldn't we all hope to see the OP to have this "condition" go away simply

I'm holding out hope for the OP's engine. I'd like to see what he gets with the external oil cooler removed. For me, I'm planning to break-down one of my two 1.7 engines I have and start building a second. I want to be able to hot swap engine + transmission, if anything should happen.

Glad to hear it worked out. My secondary relief valve rod is coming Tuesday.

I know the senders should ground through the braided hose, but for shits and giggles run a ground wire to the senders.
Did you try the Tangerine oil booster?
Your positive you didn't swap in/out hose on the sandwich adapter?

In and out hoses were correct, double checked on install. Better to use a sandwich plate with out a thermostat and install an inline thermostat?

Better to not use external cooler Sorry . . . couldn't help myself.

Seriously hoping that your pressures go up . . . Hate to see anyone going though low oil pressure troubles.

Yeah, give her a go without the cooler. Is the original cooler still functional? I wonder about the interaction of two coolers opening up as the oil heats.

+1, I will second this

Original cooler is good. Secondary oil pressure relief valve rod has been delayed until Wednesday.

Disconnected the oil cooler and removed the sandwich plate. Removed the secondary oil pressure relief valve spring and installed the rod from EMW. Took it out for a short drive. Oil pressure started at at 60lbs. @ 70*. When the oil temp gauge read just under 180*, the oil pressure was reading 22lbs. at 2800 rpm. Calling my machinist tomorrow and see where we go from here. I may have him build the bottom end and I will finish the top end.

If pressure drops rapidly after 180F OT I instantly suspect an issue with an internal clearance. I can't remember a time when that suspicion was incorrect if the bypass valves were working correctly.

Thanks, Jake. Looks like a tear down is in order.

Update:

Just finished rebuilding the engine. Replaced all the bearings except for the cam. (less than 100 miles)

Specs:

Rod bearings .0015 .0008-.006
Connecting rod side clearance .011 .004-.0276
Piston pin .0012
Main bearings 1,3 .003 .0016-.007
2 .003 .0011-.0066
4 .0061 .0019-.0074
Crankshaft end play .0041 .0027-.005

Camshaft end float .004 .0016-.0063

Main oil relief valve, Tangerine racing
Secondary oil relief plugged with EMW solid rod.

Shadek 26mm blueprinted oil pump

Joe Gibbs 15w50 oil

Outside temp, 80* cold oil pressure is 70#

Oil pressure when hot is 18# at 2800 rpm!!!



Just called my machinest. .003 main bearing clearance, though well within spec, is too big. He said aluminum case engines should be running under .002. He suggested buying a set of bearings and having them coated to tighten up the clearances.

Who's measuring the main bearing clearances and by what method?

I've had some variances in measurement between telescoping snap gauges (less accurate) and an actual bore gauge.

You can actually Plastigauge the middle split bearing as a rationality check.

.003" of clearance on the mains should not be causing you those sort of pressure problems. Why is #4 at 0.006"? I don't have the Tom Wilson book at hand but if I recall, 0.007" isn't the recommended upper spec for bearing clearance -- Its the absolute wear limit.

What are your camshaft bearing clearances?


On separate topic - are you sure pump is good? Have you actually measured the oil pump? Is the cover plate flat? Have you measured end clearance between the pump gears and the cover? Is there any wiggle on the gear shafts? Have you measured gear backlash?

I'm not a fan of type 1 pumps (don't hate me ). Are you sure it was machined properly? How much clearance between the pump body and the case?

What I'm getting at is could the pump itself be having high internal pumping loss and/or losing pressure between the pump body and the case?

You say that your oil pump is blueprinted but did you o-ring the body of the pump to prevent air being sucked internally, that has been an issue with those pumps.

The pump was block sanded on a glass plate to make the pump body flush with the gears. The cover was also polished on the glass so it was perfectly flat.. it has a .002 gasket, no sealer, between the cover and the body. Something is expanding when it gets hot causing excessive clearance. The problem is you can only buy Silver Line steel backed bearings, so I can't compare them to something else. The crankshaft and bearing clearances were measured with a bore gauge and a micrometer.

That sucks. I would try to reduce the variables as much as you can. Can you go back to stock oil valves? Oil cooler? If you can limit it to the bearings and pump that would help.

We had this problem years ago , when the engine got hot the oil pressure would go down. WE figured an aluminum case and a steel (aftermarket I think Melling) pump were expanding at different rates and letting oil seep back through the pump .Engine great for years.

I was searching engine bearings. My machinist said .002 or less for bearing clearance. Mine is .003, but that does not include bearing crush. I torqued the case through bolts to 24 ft. lbs. according to the Haines manual. Ian Karr's video he torqued them to 25. would 1 ft lb make a big difference in bearing crush? Should I replace the Shadek pump with the CB Performance pump? My only other option would be to tear down the motor again, buy .010 under size bearings and have the crank ground to fit the bearings. My crank is 2.6310. right to spec???

What about that #4 at 0.006" is that a typo?

What are camshaft bearing clearances?

The difference between 0.002" and 0.003" isn't what's causing your problem.

Main journals are 2.3609 - 2.3617 inches for #1 - 3
Main Journal #4 is 1.5737" - 1.5748 for #4

I'm assuming you have typo above?

2.3610 is at the low end. Wouldn't want that with a high end case bore.

Also did you measure your case bores on both axis to make sure they are round and not pounded out?

I went over my notes this morning and measured the old bearings I removed with less than 100 miles on them. I am at .0025 to .0027 clearance. The bearings are round. At this point I am ruling out main bearings and clearances. My focus is on the Shadek oil pump. The high performance book calls for a 2.755-2.7565 O.D. My pump measured 2.750. I am going to replace the pump with a CB Performance 1849 Maxi Pump 1-914. I am guessing the oil pressure is dropping due to the excess clearance and possibly leaking oil into the case.

I was advised a batch of Shadek pumps were under sized, mine is too. I used loctite 512 red sealant around the pump to help seal it. Can not hurt as I already have the pump. I installed the pump in the bottom half first and sandwiched it in place with the top case half so no to scrape off all the sealant. IF I pull my pump It gets a new one that fits. EMW will sleeve the undersized Shades pump so it fits if you need a new one. Im not sure the o-ring is the beter solution as it s right on the edge of the case . I may just pin my old stock pump and give it a once over? Hope this helps

I may just pin my old stock pump and give it a once over? -- YES!

Last thing in the world I'd be doing is screwing around with undersized T1 pumps and trying to sleeve them and/or seal them to the case with sealant.

Type 4 pump is a better overall design (all gears in double shear). I know this isn't a popular opinion.

Of course, the known weakness of the T4 pump is the tendency for the pin to migrate IF the engine is overheated. Pinning the idler shaft resolves that issue.

FYI - there was also a guy over on Samba selling very nice 30mm CNC type 4 pumps - I bought one and posted a review of it. My only critique of it was that I was disappointed they didn't pin the idler shaft either

https://www.thesamba.com/vw/classifieds/det....php?id=2450773

Post #20
http://www.914world.com/bbs2/index.php?act...=2&t=338311

Yes!

All my cases are now in storage as I prepare to move so I can't go measure one quickly. I believe the T4 oil pump OD is 2.757" on the T4 pumps. The case is slightly larger to get the pump in but as we know, they are very tight fit as they should be.

If your T1 pump OD is 2.750" you essentially have a very large bearing (or call it a leak) in your engine (analogy) who's diameter is 2.757" and is running at least 0.007" 0.0035" of clearance. This "bearing" (leak) is right at the front of the oiling system before anything else.

Water and/or oil tend to flow to path of least resistance. So oil is going to want to flow out that gap BEFORE it ever goes anywhere else with tighter clearances and/or has to go though a longer torturous flow path through an oil filter, your external cooler and all associated plumbing, and then the oil galleys.

Then there is the issue that the oil pump inlet is also trying to draw oil out of the sump though this same clearance. Not good. At best, what it is doing is short circuiting the pump itself with a larger internal bypass directly from pump outlet to pump inlet. At worst, the inlet starts to suck some air though this clearance.

Good find.

It's possible your low oil pressure was simply the pump being too loose in the case. It should be a tight fit. I have never measured ID vs OD but know they can be difficult to pull a pump and should never slide in easily.

Hope that's your issue

Received the CB Performance 1829 Maxi Pump 1 914/T-4 Old pump O.D. measured 2.753. CB pump measures 2.7555. Both are Schadek pumps. CB pump is modified, see pictures. I am not using cast aluminum cover, going to use my old steel cover instead. Steel gears on steel is better than steel gears on cast aluminum. The CB Performance pump is on the right with the hole. Hope this solves the low oil pressure problem. Click to view attachment Click to view attachment Click to view attachment Click to view attachment

How does it fit into the case?
Should not slide in - out easily

Had to tap it in with a rubber mallet and a 2x4 as usual.

CB is still 0.001" under size. I dug a T4 pump out of storage. 2.7565"

Sure would be nice if vendors would simply duplicate OEM dimensions.

Should be a world better than the old pump which grossly under size at 2.753".

Buttoned up the engine last night and took it out for a spin this morning. Problem solved
Oil pressure cold was almost 80lbs. Oil temp just above 180*, oil pressure was 35lbs at 3000 rpm. At 3500 it was 38lbs. You are right, for a custom pump, the specs should be at the high side, 2.7565. So the moral of the story is don't assume anything. Check everything twice. I notice a lot of 2056 builds using Schadek pumps are complaining about low oil pressure.

for perseverance.

Glad it was "simple" and didn't involve line boring and/or grinding the crankshaft.

Congrats, enjoy in good health

Was the problem with a small OD of the pump? or ??

Small OD of the pump.

Congrats Geezer914! So great to hear!

Great news. What a relief that must be.

Congrats! So...even though you had to use the 2x4 and mallet to get it in, the original pump was loose? Was it tightt just in a spot or two, allowing the oil to seep around?

Had to tap that one in too. Hard to tell the difference of .002 with a hammer and a 2x4! . Relieved is to say the least! Thanks for all the replies and support.

Air in the oil gauge that made me wonder and not good?,most likely caused by the pump not being a tight fit in the case ,reckon that was a red flag right there ,regardless you now have the result you need,well done .
I remember reading on the samba about poor pump fit with some T1 pumps used in T4 application .
Time to go out and do some ,cheers.

@geezer914 I just received the CB pump. The OD was right in the middle of the manual specs. My question is, did you install using the fat gasket between the body and case?

TIA

No gasket between the body and the case.

Some very unwanted down time has been allowing me to catch up on some very interesting threads that I’ve missed, this one included.

@Geezer914

Glad you got all this business ciphered, going through all that hassle couldn’t have been fun. I’m curious about the pump, while my pressure is good, I believe my last oil leak is coming from the oil pump itself. I despise oil leaks, so annoying to leave drops when parked, not to mention what blows back onto the engine under way.

@Superhawk996

I gotta agree with Geezer, I’ve found an oil cooler to be very beneficial here on the east coast if for no other reason than to eliminate the heat soak that would occur on hot days while sitting in Effn NY traffic! Really the only time that I’ve needed it, it’s also a Setrab unit with a fan that turns on at 190°, along with a Mocal filter adapter that opens at 180°

Does it still get hot? Absolutely, but as was the case last weekend I didn’t see anything over 230ish, as verified by both the VDO gauge and a Mainley dipstick gauge (very neat item)

Anyway, it’s a little peace of mind that it provides, as we all know 50 year old air cooled stuff can be both fun and frustrating at times. But I suppose that’s what makes it so interesting...


Last note, get your colonoscopies gents. Cancer really does suck.

My pump was leaking from the 4 nuts holding the front cover. Removed each nut and applied a little of "The Right Stuff" gasket sealer. No leaks. On the CB Performance pump, I didn't use the aluminum cover, I used a steel cover that was sanded flat with sandpaper on a sheet of glass. Gasket only on the cover was .002 and no sealant.

Double post