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Discussion Starter #1
Hi... I have an '81 Spider that is equipped with the SPICA injection system. It recently encountered a problem with the oil pressure dropping to 0 and the oil warning light illuminating after running for a few minutes. It was suggested to me that one of the temp sensors may be bad (reading the engine is cold) and the fuel system is flooding the engine and dumping fuel into the oil. Has anyone encountered this? Any thoughts on a fix or a way I can test that the SPICA is functioning correctly?
 

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Even if the Thermostatic Actuator were inoperative and sending an "engine cold" signal to the injection pump, the fuel would not be flooding into the oil sump. The engine would just run badly (very rich) after it warmed up.

To check if the Thermostatic Actuator is functioning correctly, take the air cleaner off and check the distance between the throttle arm and the reference screw (on rear of pump) is no more than .019" with the engine fully warmed up (at least 180 F).

Now, if the injection pump plungers are extremely worn, THAT can cause fuel to leak into the oil sump and dilute the oil, perhaps causing a lower oil pressure.

To test for fuel seepage see the thread "Puff of smoke while shifting."

Is the oil low pressure warning light coming on at idle only, or even when the engine is running off-idle? Does the oil pressure drop even before the engine warms up? If the oil is not severely diluted with oil, it may be that an oil passage plug in the crankshaft has come out. If the problem happened "all of a sudden," that would point towards that cause.
 

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Good call on the crankplug(s) John! They're the #1 cause for a sudden drop in oil pressure (in an Alfa L4 anyway). Fairly easy fix too as they can be replaced with the engine in the car.
I don't think it's an oil dilution problem because 1) the low pressure reading was not gradual but recent and 2) I don't think there's enough room in the crankcase for enough fuel to dilute the oil enough to cause zero pressure.

Nice to have another Joiseyite on the BB!! Welcome.
 

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I agree Jim. If the oil was diluted that much, the quantity would be increased A LOT, and the smell would be REALLY hard to ignore.
 

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Discussion Starter #5
Thanks for the great help. Let me try to go into more detail. At startup (cold), the oil level is normal and pressure is in the normal 15 to 20 range. The car idols fine and can do so for 10 min without a problem. After driving a short distance (2 miles) and then coming to a stop, the pressure gague reads 0 and the oil light comes on at idol. Increasing the RPMs does increase the pressure but it goes back to 0 at idol. If the car cools, the pressure returns to normal. I recently acquired the car so I have no idea of it's service record. In addition, this is my 1st exprience with the SPICA system so I wasn't sure if I needed to service something on the pump. Any insight is a great help. Thanks.
Eric
 

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Roadtrip said:
To check if the Thermostatic Actuator is functioning correctly, take the air cleaner off and check the distance between the throttle arm and the reference screw (on rear of pump) is no more than .019" with the engine fully warmed up (at least 180 F).
Welcome to AlfaBB.com Spencer! You've gotta post some pictures of you Spider in the Photo Gallery. I used to own an '81 Spider. I miss the open top driving.

Just a quick note RT. The airbox on '80 and '81 Spiders is on the driver's side. There's an aluminum intake plenum over the Spica pump. I don't think you can see the rear of the pump through the plenum intake pipes that attach to the head.
 

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SpencerTurtle1 said:
At startup (cold), the oil level is normal and pressure is in the normal 15 to 20 range.
Cold startup oil pressure should be 60PSI or more and hot pressure is 55 minimum at speed. Sure sounds like one or two crankplugs have come out. I would have suspected a faulty oil pressure gauge reading except that the low oil pressure light comes on as well. These are two entirely separate circuits so the likelyhood of both circuits being faulty is quite remote. But I'd check the pressure with a mechanical pressure gauge just to be sure.
 

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Gotta agree with Jim, you have probably lost
one or two crank plugs. I had the same problem
happen to my Spider with very similar symtoms.

Here's a question for Jim. I know you can replace
the plugs with the engine in the car, but can they
be tapped and use threaded pugs whith the engine
in the car?

The fuel in the oil may be blow by from worn rings.
Have you done a compression test? Also is the car
using more than 1 quart to 500 miles? Alfa's do
burn some oil, but should not blow smoke, or use
more than the above amount.
 

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Discussion Starter #9
Humm.. I'm not blowing any smoke but I can not drive it more then a few miles to see if it's burning oil. I suspect my gagues are correct so I will look into the "crankplugs". I ran that past my Alfa parts guy and my mechanic (non-Alfa guy) and they both had not heard the term. My parts guy asked if it was the "cigarette seals" or if they ha a different name? Aslo, If you have the time, I would love to know if indeed they can be put in without pulling the engine. Thanks fo the help.
 

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Keven said:
...I know you can replace
the plugs with the engine in the car, but can they
be tapped and use threaded pugs whith the engine
in the car?
No. There's not enough 'swinging room' to properly line up the tap. Plus, there's a chance that a metal chip or two will stay in the crank and REALLY screw things up. And then there's the possible weight difference between the metal screw-ins and the aluminum stake-ins to throw off the crank balance.....

SpencerTurtle1,
The cigarette seals are two oil seals fitted between the rear main bearing cap and the block. The crankshaft plugs are small, round tapered pieces of aluminum that are driven into the crank counterweights and staked in place. I think there's a total 6 of 'em. I've found that usually only the rear most plug comes out (the hardest to get to of course). Replacement requires removal of the oilpans. I'll post a pic of one later today. If they are indeed the problem, and you can't find any, I have some I'll donate.
 

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I had an Alfetta that lost 2 crank plugs- another symptom is a lot of foam in the oil just after running it. THere will be bubbles on the dipstick.

That car was one that I REALLY wished I had been a member of AROC with. 15 years ago when I first bought it, the only thing out there was the club..

So when the oil pressure dropped off, I never knew to check that. All I did was tighted down a loose oil pump. Which was a large shock to see... But I thought that the little piece of aluminum I found was from something else.

Thankfully, I didn't cause enough damage to really hurt the engine.

Back on to this problem- I didn't think you could remove the oil pan from a Spider in the car...

Eric
 

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Sure sounds like a classic case of a blown crank plug to me. Low oil pressure at startup decreasing rapidly to zero as the engine warms up.

Check this page on the KC Alfa Owners Club. One of their member posted an outstanding series on an engine rebuild, including this page showing the aluminum crankshaft plugs and setscrew replacements. He also show how he did a mod to drill oil passages for direct oiling of the #2 and #4 bearings. A really outstanding series by a member of the KCAROC.

http://kcaroc.pcbs.net/techses/89rebuild0/thumbs.asp
 

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Pretty good writeup. Thanks for the link RT.
Here's a pic of the plugs I have. They measure 0.27" (6.86mm) at the thick end and taper to 0.223" (5.66) at the other. Length is 0.79" (20mm). They are included in this engine lockplate kit for a 1750. The two black things above the caliper are cigarette seals.
 

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Discussion Starter #14
Thanks for he info... this seems great. Is there any way I can diagnose the crankplugs difinitively without taking the engine apart? I'm doing some emission and compression tests today as well as giving it a change of oil but I'd be happy to do any othe tests that might be useful. Thanks for the great help.
 

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About the only way I know you can positively check is to visually inspect. If you take off the lower oil pan, you might find an aluminum plug, which would be a definitive answer. The plug might be also up on the upper oil pan shelf, but you can probably reach up there or probe with a coat hanger to be sure one isn't hiding up there. Removing the lower oil pan is quick and easy.

Hopefully, that's all the problem is since it'll be the most inexpensive thing to fix.
 

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Thanks. Before I start pulling the engine, I figured I'd try a few things as I realized for starters, I didn't know what weight oil was in the engine. So far, popping 20 50 in seems to have made a drastic change in the pressure. Seems to be a little rough on the cold start but drivable when it's warm. I'll keep everyone posted and thanks for the great feedback.
 

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Discussion Starter #17
End of the story...... Thanks to everyone for all the help. Alfa guys definately are great.

After some tweeking, I got the car over to PapaJam for what I had thought would be som SPICA investigation. I had had the car at 2 different mechanics over the past year and the consensus was fuel problems. I knew the SPICA had oil pass through it so I thought this could be the root of all my problems. Much to my surprise, with a little time unde the hood, PapaJam noticed that the ignition timing was 68 degrees off and the injection was 180 degrees off(Injecting fuel whenthe cylender was on exhaust). All the marks just didn't line up so we pulled the valve cover to find the cams 180 degrees off. After rotating them and doing a valve job, the engine purrs like a cat. The oil pressure seemed to be related to the poor performance of the engine and th heat that was generated.

A side note: I have a MSD ignition system that I installed to get the engine running to the point that I could drive it to PapaJam. I was a little skeptical at first that this $250 investment would make a difference but it truely does make the engine perform even when there is something seriously wrong. So a definate endorsement.

Thanks to everyone and I'll have some new pics posted soon.
Thanks
Eric
 

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Eric - Thanks for the PM. Wow, it sound like the PO or his mechanic was totally clueless. With every timing point of the engine WAY-off, I'm surprised that it even started in the first place. Lucky it didn't bend up the valves.

Good job. Another Alfa saved!
 
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