Series I temp sender questions

[SIVAllan]

I am hooking up gauges on a Series I v6 conversion that's been underway off 'n on for quite a while.

A couple of questions linger as I address hooking up the temperature sender.

The late Alpine gauge being used draws power on late series Alpines from an under-the-dash current regulator.

Series I Alpines don't have such a regulator.

Does one need to be added, or can the one wire alternator be trusted to deliver correct, steady current?

Secondly, I have a UNIPART 324 sender. The package states it is part number "GTR105."

It fits the 2.8l engine's gooseneck. It has no paperwork and has been on a shelf so long I forget where it
came from .

Does anyone know it this part will pair corretly with a late series Alpine temp gauge?

Many thanks.

 

[Tom H]

Allan,

Yes, the later series gauges require the voltage stabilizer. That device holds the voltage for the two gauges at 10 V. No problem to add one to your car. You can get modern solid-state replacement types from several sources. The modern replacement ones are polarity dependent. If your Alpine is now Neg earth, be sure to order such.

Regarding the sender I don't know what the ones you have are, but it seems quite unlikely that out of the hundreds of different senders, this one would be a match, unless someone selected it as a match. The information I have on the sender for use with the later gauges is that at 25ºC = 650 ohms and at 100ºC = 43 ohms. I am pretty sure that SS stocks senders that match the later gauges, but I don't thing the threads match the Ford housing. Here's a link to an article Mike Hartman and I wrote about these gauges:

http://mhartman.net/files/sunbeam/fuel & temp gauges.pdf.

There are thread adapters available. Not sure there is an adapter to match the Alpine sender to a Ford housing. Maybe others have knowledge of such.

Tom

 

[SIVAllan]

Tom, thanks.

 

[hartmandm]

Allan,

I did some testing of temp senders for DanR and his V6 conversions. He was looking for a sender that had 1/8 NPT threads, so it would fit in the V6 Offy manifold and would work with the later series temp gauges. I don't know if 1/8 NPT threads are what you need ... Dan sent me some senders he had, and then I tested two commercially available senders. The results of those two commercially available senders are on pages 11, 12, and 13 in this write-up: http://mhartman.net/files/sunbeam/Senders Report.pdf

Mike

 

[SIVAllan]

I ordered a voltage stabilizer so that should arrive sooner or later.

I also stopped by Summit to order a temperature sender.

The New Vintage USA 99005-40 sender has been superceeded. Summit staff didn't know if the replacement is to the
same spec so I got a VDO unit, which should do fine.

These should take the v6 conversion a big step forward.

 

[SIVAllan]

Rocking along on the v6 convesion and thankful for all the help and advice

One question - when it's said in the article that that senders fit the Offy manifold is the intent to say that the senders fit the gooseneck in front of the Offy manifold?

The sender I brought home from Summit doesn't fit. It's way to small for the stock 2.8l gooseneck. Maybe there's an adaptor, maybe Summit and I picked an incorrect sender.

The picture shows side-by-side a GTR 101 sender removed from the 2.8l gooseneck and the Summit sender NVU-99320-04.

So, back to Summit

 

[hartmandm]

Allan,

My recollection is Dan was fitting the sender into a hole in the Offy manifold. That is why he was looking for a sender with 1/8 NPT size threads.

Can you measure the thread OD and TPI for the sender you currently have in the gooseneck? I might be able to find an equivalent sender in that size.

And which VDO part number did you purchase from Summit? The 140-280 mark on the sender has me worried it might not have been the correct sender, though it does look like it was the 1/8 NPT size based on your photo.

Mike

 

[SIVAllan]

Allan,

My recollection is Dan was fitting the sender into a hole in the Offy manifold. That is why he was looking for a sender with 1/8 NPT size threads.

Can you measure the thread OD and TPI for the sender you currently have in the gooseneck? I might be able to find an equivalent sender in that size.

And which VDO part number did you purchase from Summit? The 140-280 mark on the sender has me worried it might not have been the correct sender, though it does look like it was the 1/8 NPT size based on your photo.

Mike

Mike,

The sender has 7 threads extending over 1/4 inch.

I took the sender to a hardware store to see if they had a pipe plug to match it. They selected a 3/8 plug
but it only goes in partially so I am thinking the gooseneck threads are metric.

The VDO sender is NVU-99320-04.

The stock gooseneck isn't as neat looking as the aftermarket gooseneck as it has three openings. However I'm ok with it.

 

[hartmandm]

Allan,

NVU-99320-04 is a New Vintage sender part number, not a VDO part number. I don't think that sender would have had the right resistance curve if it did fit.

I'm guessing you don't have a thread gauge (SAE & metric) or a caliper to measure the existing sender's TPI and thread OD?

I'm hoping someone on the forum might know the stock temp sender diameter and TPI.

Mike

 

[SIVAllan]

Allan,

NVU-99320-04 is a New Vintage sender part number, not a VDO part number. I don't think that sender would have had the right resistance curve if it did fit.

I'm guessing you don't have a thread gauge (SAE & metric) or a caliper to measure the existing sender's TPI and thread OD?

I'm hoping someone on the forum might know the stock temp sender diameter and TPI.

Mike

That's correct.

Summit initially provided an incorrect New Vintage USA 99005-40 sender. I didn't look at it until I was on the way home. It needed a special fitting to connect to a wire so I turned around and took it back.

That was the best they could do so I provided the recommended VDO number as Plan B.

That was a bust as well with NVU-99320-04 emerging as an equivalent.

I was operating on the assumption the sender would fit the stock gooseneck. I don't see how it can fit
the Offy manifold as I have one installed and don't see a threaded hole. Something must be different. Doesn't matter though if the stock gooseneck is being used.

Actually I do have away to measure the thread's OD, now that I think of it. So I'll do that. I don't have a thread gauge but will check with a different hardware store.

Thanks for looking into this. I appreciate your help.

 

[loose_electron]

One additional side thought - When it is all said and done, buy an infrared thermometer gun, so you can check the temp against what the gauge says. They are a cheap tool to have, typically $20-$30

 

[SIVAllan]

Allan,

NVU-99320-04 is a New Vintage sender part number, not a VDO part number. I don't think that sender would have had the right resistance curve if it did fit.

I'm guessing you don't have a thread gauge (SAE & metric) or a caliper to measure the existing sender's TPI and thread OD?

I'm hoping someone on the forum might know the stock temp sender diameter and TPI.

Mike

Mike,

I stopped by an ACE hardware store.

ACE determined the threads are metric and that a 16 mm nut with a 1.5 pitch fits the sender.

So the sender's theads are metric, 16mm with 1.5 pitch.

 

[Tom H]

Allan, you seem focused on finding a sender that will FIT into the gooseneck. But you don't seem to understand that the sender needs to have the resistance characteristics that match the Alpine gauge. I looked up the parts you have mentioned and see no indication that it is a suitable sender for a Sunbeam Alpine gauge. Am I missing something?

 

[SIVAllan]

Allan, you seem focused on finding a sender that will FIT into the gooseneck. But you don't seem to understand that the sender needs to have the resistance characteristics that match the Alpine gauge. I looked up the parts you have mentioned and see no indication that it is a suitable sender for a Sunbeam Alpine gauge. Am I missing something?

Tom,

If a sender with the right resistance characteristics doesn't fit - what use is it?

Have you read the thread?

The question is which sender BOTH fits the stock gooseneck and has the right resistance characteristics.

 

[Tom H]

Allan, Yes, I've read the thread several times and am confused and trying to help. I see several senders mentioned, but I see nothing in any data I have found on-line for them that would suggest that they have the temp/resistance characteristics of the Alpine gauge. I am wondering how you or the dealer came to select the ones you mention. I have never personally worked on a V6 but I have read a bit on this forum, especially regarding electrical issues. I know other V6 owners have found a solution to this, but have not searched to see what the answer is. It seems easy to find a sender that would fit mechanically, just find a sender for the model of car that the gooseneck came out of. But that almost surely would not match the gauge.

I think one of the solutions I have seen is to find a sender, maybe a stock sender for a SV Alpine and fit that sender into the gooseneck you have using JB Weld and/or drilling or grinding he hole larger if needed.

Tom

 

[SIVAllan]

Thanks Tom.

I revisited a search and an earlier suggestion to solve a slight misfit (too small) of a stock late Series sender with the stock 2.8l gooseneck.

Tape plus a ground wire should do the trick.

I don’t see any reason a stock late Series sender plus a repo Rootes voltage stabilizer plus a late series gauge won’t work.

 

[hartmandm]

There are two VDO senders in their brochure that should have the right M16 x 1.5 thread size and the same temperature - resistance curve as the VDO sender that I documented in the Senders Report document. However, I only see one of the two senders on the VDO web site. Part 323 417 - https://www.vdo-gauges.com/sensors/...sensor-only/250-f-120-c-m16x1-5-801-1-29.html

Available at Jegs and some other online sellers. https://www.jegs.com/i/VDO/918/323-417/10002/-1

Mike

 

[Tom H]

I don’t see any reason a stock late Series sender plus a repo Rootes voltage stabilizer plus a late series gauge won’t work.

Exactly. That should work. But seems a better idea to follow Mike Hartman's suggestion since it seems he has found, by testing, a matching sender for that gauge that also fits your gooseneck threads.

 

[hartmandm]

Allan,

Did you ever sort your sender issue?

Mike

 

[SIVAllan]

Allan,

Did you ever sort your sender issue?

Mike

No. The engine failed on a test drive, blowing one or both head gaskets, or worse.

I'm pretty disgusted and haven't pulled it yet to do an autopsy.

It looks like the goose-neck attaching the lower radiator hose failed or the hose split catastrophically, or something
as yet unknown occurred in that area, allowing sudden, undetected, massive loss of coolant.

I have a '72 Harley Sportster barn find bike (1000cc XLH) to play with and maybe ride out west if I can get it sorted. Right now the Alpine just went to the back of the line .

Mike, I appreciate your help with the issue of which sender works/fits the stock 2.8l engine goose-neck, and with keeping the thread on track.

I'll get back to this in the Fall, hopefully. Short blocks are available for $900ish for later 2.8l engines, if my early block fails a magnaflux for cracks. I also have a stack of heads if needed but would hate to loose one of the professionally worked heads currently on the engine.