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turbogrill

L28 engine - tough?

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During an endurance race we lost all the coolant without knowing it. The driver pulled in when the oil pressure lamp went bananas. Was oil squirting from where the the oil filter sits and the dipstick was so hot it burned a hole in a cloth. It seemed like the oil was boiling.

I thought this engine was done and accounted for. 

 

Fixed the coolant leakage, drained the oil and let it cool down. We sent it back out to the track and the engine was fine, maybe a some loss of power. But the engine lasted at least for the reminder of 8hours of racing.

 

Is this normal for engines or is the L28 extra tough? I would think something like this would be the death for an engine.

 

 

(It occurred to me that having only water temp is pretty useless unless you have a water pressure sensor or an oil temp sensor).

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The L blocks are pretty tough and only show light signs of wear in cylinders. I had an L28 engine that had 250k miles on it.. I took it apart to replace the bearings and do a rebuild on it. Removed the bearing caps and they had no wear on the bearings, crankshaft, or cylinders. The cylinder walls still had the original cross hatching in them after all those miles... :D   I didn't even need to replace the bearings.. but i did..

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Completely empty, the water temp was normal since there was no water. Also racing so 100% load on the engine.

 

Driver went into the pit because the oil pressure lamp wnet crazy.

I will now install an oil temp :)

 

You might want to check your water temp gauge.  With no coolant it should read ambient air temp, not the ~180 of coolant.  You should have seen the temp drop drastically, buiring the needle to cold.

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You might want to check your water temp gauge.  With no coolant it should read ambient air temp, not the ~180 of coolant.  You should have seen the temp drop drastically, buiring the needle to cold.

 

Doesn't always happen that way. You can blow a hose, lose most of the coolant and the water temp stays at 100 c, which isn't all that hot. Steam heats the temp sensor and gives a false reading. Motor can be melting down and temp stays at 100C. Happened on my Audi recently. I've seen it a couple of other times on race motors. Steam will nicely fool a water Temp sender.

 

Catastrophic loss of coolant or W/Pump failure can cause this issue. Rare... but it happens. 

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To me, race engines are not disposable, because I spend a lot of money and time making them perfect, or having them made perfect. Therefore, early warning devices are mandatory ESPECIALLY if you're going to have drivers in the car that aren't particularly familiar with it! Twice in the last 3 years, the early warning devices have saved me big time and the last time was at the 2016 SCCA National Championships at Mid Ohio. To make a long story short, I lost my dry sump oil pump belt. In car data shows the engine ran 14 seconds after the OP dropped to Zero. I literally thought I caught it immediately. I run Redline synthetic oil and cutting the oil filter showed no particles, Phew! We went on to podium. This save was because of a simple oil pressure light mounted in a visible location and shielded from the overhead sun. I also have a water pressure warning lamp. I believe this to be even better than a water temp warning. If there's a pinhole in the system, the lamp will light and you can chase the issue before it burns up.

 

Regards,

 

Greg Ira

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Back when I was a kid, I worked at a place in Ft Lauderdale called the Z car Center. (3 guesses what they specialized in) I was driving a '79 280ZX at the time. I had just picked up my son from daycare and dropped him off at home, and was on my way back to the shop to finish up a few more hours of work. It was raining cats and dogs, and there was plenty of water in the road. I came to a flooded section, and the water came up to the bottom of the doors, but I was young and fearless so I decided that I could make it through. (I was like 21 or 22, so still 'technically' retarded) I was ... not correct. The water got up to the hood, there was a hell of a bang, and the engine stopped dead. I slogged the rest of the way to the shop, Jeff got the truck, and we dragged her into the shop, where we pulled the plugs out and turned the engine over. Water shot across the shop from all 6 cylinders, and Jeff told me that I'd probably need to rebuild it. I was sad. The next morning I got a ride in to the shop, put the plugs back in, and tried to start her up. I remember that she sounded like a steam engine, and flames were shooting out the side of the block from Numbers 5 and six, where 2 chunks of head gasket had been blown out the side of the block... but she ran. At the time,. it was the most badass thing I'd ever seen. For the next few days, until we replaced the head gasket (which was all the repair she needed) she was driven in and out of the shop daily. That's when I fell in love, and decided it was the only kind of car I wanted to own. ... So the short version is that yeah, I'd say the L28 is absolutely one of the toughest engine ever made. 

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Good point, I will replace my oil pressure light with a strong blinking led.

 

What about water pressure? What sensor and where?

When we raced sportsman camaros we had two lights: water pressure and oil pressure one on either side of the tach, with the shift light above the tach...right in your line of sight.

 

There were gauges for both water and oil off towards the center of the dash, you looked at them around start time and during warmup or cooldown....

 

As I recall, water pressure  ran 45-60 psi in the block and the Hobbs switch was set for 30# (we ran a 24# Pressure Cap with straight water. The Hobbs switch should be set to come on above cap pressure and below operating pressure at fast idle...for the life of me I can't remember that pressure now. I remember the water light was  on when we started, and for a while until we warmed up, unless we revved the engine a bit. 

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