K series oil pressure sender

[Redbullwings]

I'm trying to source a replacement oil pressure sender for my 1.8 vvc k series, but am struggling to find one. Both caterham and redline are out of stock, and although I'm pretty sure it's at fault I'm desperate to get one before next weekend as I'm planning to drive to goodwood again.

does anyone have a suggestion for an alternative supplier?

thanks

[Alan Archer]

I got one sent to me from Jon at Millwood Cars only last week, I don't know if he has some in stock or if he got it from CC, might be worth giving him a shout though. 

[SM25T]

Change to a mechanical gauge ..... complete system for about the same price as one electrical sender. Much more reliable.

[Redbullwings]

thanks guys.

with the mechanical gauge, and suggestions on something compatible? ive no idea what size the thread is on the K series

[SM25T]

Early cars M10. Mine is a 2002 VVC and is M12. You need an adaptor from whichever you have to the 1/8" NPT that will probably be on the connector to the capillary hose to the gauge.

[john milner]

M12 also for my 2003 VVC. Stack seems to be the most common choice.

[SM25T]

Think Auto seem to be the supplier of choice for mech gauge, capillary hose and fittings. I used nylon capillary hose and ran it inside a thick walled PVC screenwash hose for mechanical protection. Up the offside of the engine bay and through the big grommet on top of the tunnel forward of the gear lever

[Jonathan Kay]

Morning, Ian.

There's obviously a lot of interest in this modification. It would be great if you could write a Guide with all the bits and sources and threads and photos. I think it's all in the forums already. 

Jonathan

[Redbullwings]

Ive just spoken to Merlin motorsport who say they can make up a braided hose to a length i give them, provide the gauge and adaptor nut all for £74 + vat

ill probably go for the stack gauge, but will list all the parts once ive done it.

 

[Silver Machine]

Currently fitting one amongst several other jobs. In its most simple form you will need a double male threaded adaptor that screws into the place your sender used to be. You then attach your tubing to this and the other end of the tubing to the new mechanical oil pressure gauge.

Some folk use a T piece instead of the double male adapter so they can have the mechanical gauge and a low pressure warning light.

Some run a shorter length of tubing from the site of the original oil pressure sensor to a T piece located less near the underneath of the car and then complete the system as in one of the above.

 

 

 

 

[timbo297]

We have stock of the correct replacement sender or a mechanical gauge conversion , just give me a ring at Sevens & Classics .

tim 

 

[Jonathan Kay]

tim: I think that many of us might be put off doing the mechanical gauge conversion by finding the correctly threaded bits etc. (Does it differ between 7s?) Do you offer it as a single order with a bit of handholding?

Thanks

Jonathan

[Redbullwings]

Ive now completed the conversion, here's how it went.

I decided i wanted a braided hose rather than plastic, so threaded some mains flex through the hole at the front of the tunnel and routed it to the sender. Rather than coiling a load of slack i wanted an exact fit. The length was 1665mm.

I ordered the bits from Merlin Motorsport yesterday lunchtime, and they arrived today :) they also made up the hose to length. 

the bits were as follows:

1 x adaptor M12x1.5 x 1/8BSP

Goodridge Stainless steel braid hose with fittings

1 x racetech 100 PSI oil pressure gauge

​My first choice was the stack gauge, but apparently this needs an additional adaptor, so i went for simplicity. The one thing id say about the Racetech gauge is its quite heavy compared to the original caterham and a touch on the agricultural side. Once fitted its fine. talking of weight, i weighed the hose out of interest and its 150g.

Then it was on to fitting.

I threaded the hose through and put some PTFE tape around both threads on the adaptor. With the front jacked up, i threw an old baby top and tail wash tub under the old sensor to catch the oil (i knew it would come in handy) One tip before you remove the old sender, have all the bits to hand so you limit the oil loss.

the adaptor came with a small gasket that went into the hose, and i took the old copper washer off the original sender and slid it on the M12 end of the adaptor. After tightening it all up it was in with the gauge. I didnt bother rewiring the light, but just used the old one, as its a straight swap.

with everthing in place i fired it up and was pleased to see it working. 60-65psi on idle. Turning the engine off i checked for leaks, and i bloody had one. tightening up the adaptor didnt stop it so i have to undo everything again. the problem was the original sender has a large flat surface so the washer has plenty to seal on. with an adaptor it floats around a bit, so is difficult to centre. what i needed was a better fitting washer. With Halford shut and itchy fingers i went about making one from a bit of flattened copper pipe, a hole cutter, 10mm drill and a file. 10 mins later i had a perfectly fitting washer.

im not sure if there is one available for the adaptor, but doing it again id ask for one.

this is the washer that came off the old sender

the finished item, before i cable tied the hose and old lead away

And one of the fittied gauge

A satisfying job, although would have been a lot quicker if id got a copper washer for the adaptor.

[pensioner]

ordered one from merlin but with a stack gauge after your comments and with a copper washer.

Will fit after I replace the Heater Matrix which sprang a leak yesterday. New one ordered.

[rob spencer]

Have a look at this list of parts from Think Automotive http://www.lotus7.club/guides/parts-accessories-and-spares/remote-oil-pressure-sender-parts-list

[Rob Walker]

I have just fitted the Mocal mechanical gauge last week and had the same on my previous 7.  Merlin supplied:-     Adapter M12 X 1.5 X 1/8th BSP male/male

                     Mocal 52 mm Oil pressure Gauge  0-100 PSI

                      Oil pressure pipe 1.5Metres long

total cost inc vat and delivery £53.38.  The Mocal gauge is a pretty good match for the Caterham instrements and the caterham gauge illumination bulb/ fitting also fits the Mocal so no electrical mods needed.  Fitting is a 30minute job easy.

For those with a faulty electrical sender its possible to carefully prise open the sender and you will probably find that the winding bobin or reostat has brocken free of its fixings, you can refix using epoxy then re-swage the case and it will work again

 

Cheerio  Rob

[john milner]

Mine needed a M12 adaptor at the filter but I believe that some need M10. I fitted a Stack ST3101 gauge (Demon Tweeks) which included a M10 and all other parts so I needed to buy a M12 adaptor separately. The Stack kit includes a very cheap looking plastic pipe which took a few years to start leaking at the filter fitting. I have now replaced the plastic pipe with a go faster braided pipe from Merlin. The braided pipe is very nice but was nearly twice the price of the complete Stack kit.

[Brian Deacon]

I have just fitted the Mocal gauge from Merlin. A point to note. If you get a 1.5m oil pipe it has to go through the rubber grommet just forward of the gear lever.  An easier route is through the grommet near the pedal box, but this needs a longer pipe, probably at least a 1.75m pipe.

Easy job. But my gauge only drops if I tap the glass so waiting for replacement. Much better than the electric version.

[pensioner]

Thats interesting, I fitted a mechanical Stack gauge last week, worked ok for a couple of days, and now 'sticks', and shows the same pressure at tickover, [too high at 50 psi] and a bit low at 3000 rpm, [55] but again, needs a tap to move the needle, did they make up a pipe for you?

Mine went through the gear lever. 

[Brian Deacon]

Hi. Yes Merlin made the pipe. Now got me thinking I might have kinked the pipe getting it through the grommet. It might just be that it lets pressure in but not out. Will move the pipe around and see if the indication then drops.

[Silver Machine]

Think this has been mentioned before but do we need to bleed the system when first installed? I am currently fitting a mechanical gauge and wondered if the air in the pipe needs to be bled out.

[pensioner]

I asked Merlin and they say no

[Brian Deacon]

Ref my indication sticking. It cannot be a pipe problem or tapping the glass would not make the needle drop if the pressure was still trapped in the gauge. So still awaiting a replacement..

[Silver Machine]

Thank you for the reply Pensioner. That's saved what could be a messy little task.

[Jonathan Kay]

Think this has been mentioned before but do we need to bleed the system when first installed? I am currently fitting a mechanical gauge and wondered if the air in the pipe needs to be bled out.

Andrew Revill described a big improvement in response after bleeding.

Jonathan