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Discussion Starter #981 (Edited)
Another stress thrill this morning...

With the engine suddenly harmonious, I decided to do my five-mile freeway loop to check oil temp. Short version.... by the time I pulled back into the shop the oil temp was buried against the high-temp peg. Yikes!

I opened the hood, grabbed my laser thermometer, and took a snap of everything. The thin sheet metal sump showed 86c everywhere. Engine block, radiator, front plate, oil pump... all 85c-90c.

Phew!

The first wiring harness I bought from Lionel had no built-in oil temp biasing resistor. The harness for this car has a neat fuse-holder type device with a 20 ohm resistor inside. I checked my stock and noted that I used a 31 ohm resistor in 00072.

Phew!

However, the now dead engine 1 did not show an overtemp on the oil gauge at any time. Hmmm

Dead engine 1 has an OE oil temp sensor. The sensor in the current engine #2, and in 00072, are new VDO units. Probably a different slope and/or offset.

I’ll be testing a 31 ohm resistor tomorrow.

I sent an email to Lionel (still in Spain, I think), asking why 20 ohms. He told me that was the value delivered with the resistor holder.

Oh.
 

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DPeterson3 said:
There are three sounds that all of us recognize with our eyes closed. A happy baby, a well-pleased lover, and an engine where all the parts are singing the same song.
lol, :)
Pete
 

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Discussion Starter #983 (Edited)
lol, :)
Pete
My son and I both had the same, instantaneous reaction.....

After a bunch of work, I climbed into the car, turned the ignition to “on”, let the pump fill the carbs for a moment, pumped the pedal once, engaged the starter, and..

bbrrrumumumumumumumumumum....

We both instantly looked at each other, shaped our lips in the “ooooooohhhhh” shape, and smiled.

Replace all of the above, except the sound, which instead is sort of husky and sounds like...


OoooohhhhhoohooohohohohohohhhhhhhhMmmmmmmm

We have a winner.
 
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Discussion Starter #985
Oil temp bias resistor

So.... two variables to consider adjusting. The replaceable resistor, and the sending unit. I’m going to start with the resistor.

The 20 ohm that came with the harness is more or less the length and shape of a typical Buss AGC fuse. So, I’ve made up a 31 ohm using a pig-tailed resistor, two small copper tubes, and some heat shrink.

Now to go make my five-mile loop to warm up the oil.

As I laser-thermometer tested the whole engine after the last drive, my goal is to use a biasing resistor that delivers matching coolant and oil temps after a thorough heat soak.

Report later
 

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Discussion Starter #986
I'm up to 47 ohms, and am using the original temp sender. I didn't recall I'd put that in during the engine prep for installation. At 47 ohms, I get about a 110% - 120% oil temp read in comparison to water temp. I'm used to Alfas being either even at full-soak, or oil slightly lower. Immediately upon return to the shop, I laser-temp checked everything, and the engine was overall slightly warmer, ie 93-97C, but it was even all over, and that's still acceptable for an Alfa on a very hot day. It was near 100F outside today, which might be a factor.

So, when I get back from San Fran on Thursday, I'll swap the new VDO sender in replacing the original 1959 unit, and see what ballast it requires to give me needle correlation.

I like the laser temp. Nice to have a quick confirmation.

The engine likes to be fully warm before the off-idle is perfect, but once it is, it's sewing machine smooth and ripping silk sound. Yee haw!
 

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Discussion Starter #988
Can you verify that you are using a laser temperature devise and not an infrared type.
Fair question. I’ll take a look later. Not sure what difference it would make. It shines a very bright red dot on the surface to be measured. The main point is that the temp of the radiator and upper engine block matches the temp of the oil pan, oil pump, and oil filter assembly. The cylinder head is a little hotter, and the exhaust manifold much hotter.

I’m not sure if you’re familiar with the 102 engines, but the oil pan is very thin steel, so should quickly register the temp of the oil inside.
 

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I was just curious as I realize that checking temperature over the entire engine and radiator after operation for a while with an accurate devise is just the right thing to do if you are in a rebuild or perhaps any situation where you want to be sure that your gauges are working properly. When I looked to see about adding a non contact temperature reader to add to my tool chest I saw one that said laser but it was for over $800 while all sorts of other units that read temperature without contact were available for less than $100 so I am trying to figure out exactly what would be usable and not spend any more money than I have to.
 

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Discussion Starter #990
I bought it from Harbor Freight.

It says "Infrared" on it, but also Laser Cat. 2 device".

My guess is that the laser is used for aiming, and the sensor is reading the infrared output at that location. Works fine. Typical of Horrible Freight, not expensive.
 

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My guess is that the laser is used for aiming, and the sensor is reading the infrared output at that location.
Yes, very likely. This video has some good info about spot size shows what they look like on the inside:

 

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Don,

Thanks for the info. I just have to source a decent reader that isn't expensive.
You can find them for under 20 bucks on Amazon. Even if the readings might be a couple of degrees off, it's good bang for the buck -- I suspect the error of fluid-internal temperature (oil, coolant) versus measuring externally on the case might be larger than the accuracy tolerance of the thermometer (i.e. without a probe immersed in the fluid, measurements are inherently inaccurate).

BTW, these Laser/IR thermometers are pretty good for checking temperatures remotely, e.g. the temperature of each runner at the exhaust manifold (where comparative results are more important than absolute readings), to see if one cylinder is running rich or lean.
 

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Discussion Starter #994
I buy my readers at Walmart. $15.95 for three. Then, I don’t care if they get crunched in the shop.
 

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Discussion Starter #995 (Edited)
I trailered the car up to Terry yesterday, after seeing "Hamilton" in San Fran (wow!!!!!) on Wednesday, and flying home before noon. Terry has started the top install, and straightened out some carpet issues. He plans to accomplish a little smoothing of the leather, and have it ready to return home or be picked up by Reliable in time to make Concorso by early next week.

I'll be spending the next few days finishing the display of my "Factory original horsepower delete option" and getting the story boards put together.

Car cover arrived yesterday.

Crossing fingers, I think we'll make it.

Not one year as rashly foretold, but 18 months, which is pretty good for a rusted-atoms-to-finished-car result.

Gotta be honest.... I'm not yet ready to look a new owner in the face and hand him/her the keys. I prefer to be confident in a "new car" experience as the measure of success, and although close, I'm not certain we're there yet.

Problem is, it probably requires several thousand miles to know for sure, and that would, in itself, defeat the "new car" experience. Maybe I need to offer a sort of new-car warranty to the next owner? A commitment to a fixed number of visits or work-hours to ensure a good start for its new conservator?

I did this for the previous biplane-avatar, and feel like I have a new friend as a result. Made me feel good, anyway.
 

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Discussion Starter #996
Oh. I'd really rather the new owner was a "her".
 

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Discussion Starter #998
Ya' know Div.... The money isn't really the primary concern. Yes, I'd like to be paid for my work, but being paid for an act of love and devotion sort of misses the point, yes?

I've told previous wannabe owners of my work to pi$$ off. I only work for the passion, not the money. I'll accept buyers only if I get to see their heart. I don't actually have a number for this one. Someone will understand that.

My other 102, 00072, is more thrilling. I'm amazed by the difference in the butt-o-meter feeling between a 2000 and 2300. Whoa. This is definitely the most exhilarating 2000cc Alfa I've owned (included 115s), but there's really no replacement for displacement. And, this one is oh-so-much-more civilized. Door closes are a simple, hands-free "thunk". Trunk is a simple closure, no long drop. The 60 models apparently benefited from the experimentation of 1959.

Hugs to you all.
 

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It's an interesting point about the "after care." I was watching a video about a detail shop that was concerned about the long term care of vehicles that charged a ton to do the work that they did. They required that their clients bring the car back within a month so that they could do the first wash and check the work that they had done.

Essentially you are thinking about offering the same thing. Apparently it was well received by the shop customers.

Of course, this is only possible if the geographic displacement isn't too great.

****, you got this done and it isn't even Christmas yet...
 

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Don,

If the distance allows, returning to the car from time to time to correct any failures will especially extend the pleasure of this restoration.

Congratulations for all the work done and the pitfalls foiled.

Witnessing this through this forum has been a real pleasure for all of us and I hope this has inspired many.

So a big thank you for that.

Hugs to you too !
 
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