How does a Tdi Thermostat work? Live cutaway experiment of the bypass valve working!

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[@AngusAbbott-qf8xm]

That’s so much easier to understand than a thousand words

[@overnighter]

Mike, you are right. I've never seen thermostat working in a cut like this before! Seeing thermostat working like this is awesome! And I quite like that 😊 Cheers 👍

[@BritannicaRestorations]

Thanks 👍

[@rajithrathnayake9008]

Thank you mike. I will test it again and definitely send you update.

[@BritannicaRestorations]

Sounds good!

[@jameskerr5756]

Something that I didn't think I needed to know, I now know. You know, that's worth knowing.

[@BritannicaRestorations]

Glad you know!

[@MrRobmellor]

So simple, yet so perfect. That was good Mike, it shows what needs to be seen without any words . Better understanding than showing a thermostat opening and shutting in a pan of water.Hats off to you Mike. Yorkshire Rob.

[@BritannicaRestorations]

Cheers Rob!

[@soylentblue6924]

First time in my book Mike? Simple action but it did its job! Thanks again for the vlog

[@BritannicaRestorations]

Hope you like it!

[@craig_chaznibond452]

Very interesting. I think coolant systems are generally neglected until there is a problem.

[@BritannicaRestorations]

You are right there!

[@888johnmac]

ticked as always ( also commented to help the you-tube algorithm )

[@BritannicaRestorations]

Thanks - it is all helping!

[@njenningsuk]

Great demo Mike!

[@BritannicaRestorations]

Thanks!

[@inadvisablyappliedmagic1068]

Top job mate, it makes you appreciate the varying cost of thermostats just a little bit more 👍

[@BritannicaRestorations]

Very true!

[@leighriley6277]

Bloody excellent demo, your vids should be compulsory viewing for every young apprentice 👍👍

[@BritannicaRestorations]

Thanks!

[@Viaticboston]

Agreed mate. Too often the young lads just pull broken bits off and put new bits on in the hope of fixing an issue.

[@tomjohns8498]

Awesome to show the inner workings, thank you

[@BritannicaRestorations]

Glad you enjoyed it!

[@deniscudahy4549]

What great insight to how that works 👍👍👍👍👍

[@BritannicaRestorations]

Glad you enjoyed it!

[@BritannicaRestorations]

Glad you enjoyed it

[@MrNineCherries]

Smashing. I love seeing and understanding how components work. 👍🏻

[@BritannicaRestorations]

Glad you enjoyed it!

[@RussellRF900Rrv]

That was a great insight Mike top man

[@BritannicaRestorations]

Yes - I was curious how the shut off and was this one of the over heating issues?

[@artwigwa]

Fantastic Mike :) thanks for taking the time to do the autopsy, very very interesting!

[@BritannicaRestorations]

Glad you enjoyed it!

[@SiCrewe]

Terrific demonstration. It's easy to forget that a lot of stuff on cars is smarter than we think. Just cos the thermostat is open, hot water can still find it's way back through the return if it doesn't seal properly - depending on the design of the cooling system as a whole.

[@stevedangerous3776]

Ace mike.😊

[@fionanokelly]

Very interesting experiment!!

[@BritannicaRestorations]

Thank you! Cheers!

[@harveysmith100]

Good demo though, almost like have Xray specks

[@badfinger61]

Very interesting. Good stuff Mike. Goes to show all vehicles are just the sum of their parts. For the parts makers it means their products should always be top quality.

[@BritannicaRestorations]

Very true

[@Viaticboston]

Brilliant demo Mike, I’m going to get one of the young apprentice lads to make this for the shop floor. Genuinely a really good visual aid. 👌🏻

[@jacqueshickley]

Thanks Mike. I didn't know about it blanking off the pipe. Very interesting video.

[@BritannicaRestorations]

Glad you enjoyed it

[@Jottingsfrom]

Great experiment. I never knew that’s how it worked. Thanks Mike!

[@BritannicaRestorations]

Glad to help

[@Oufg103f]

That. Was. Quality. 👍👌

[@BritannicaRestorations]

Glad you think so!

[@beccirichardson4253]

Great informative video as usual mike, and liked as requested. While you seem to be in the mood for looking inside things not usually looked inside I think a video on diagnosing (and looking inside) rear brake pressure reducing valves would go down a treat, hint hint 😉

[@BritannicaRestorations]

Right on!

[@beccirichardson4253]

Great good man, if you could throw in how to diagnose a master cylinder vs PRV then well that would just be the creme de la creme

[@750VFR]

Interesting experiment, even more interesting result Mike. 🇬🇧 🏴󠁧󠁢󠁥󠁮󠁧󠁿 😂

[@jhvorlicky]

Eh up Mike, I've said it before and I'll say it again, I love your videos!

[@BritannicaRestorations]

I appreciate that!

[@greebo7857]

Great demo Mike.

[@BritannicaRestorations]

Thanks!

[@angusabbott5615]

Enjoyed your presentation both style and content

[@BritannicaRestorations]

Much appreciated!

[@Rosbif06600]

Brilliant. Thank you. My 96 300tdi just overheatedfor the first time in 26yrs. Can't find anything wrong. New thermosrat, bled it, flushed and it overheats within 5 miles. Without the thermostat it runs at the normal temp.

[@BritannicaRestorations]

You will find the gauge will show normal, but the engine will overheat - the problem is not solved

[@123Bilko]

Jonny Ball would be so proud! 😁😁👍👍👍👍

[@BritannicaRestorations]

Nice to see how things work, rather than on paper

[@faroukwasswa3588]

This is very interesting, thanks.

[@BritannicaRestorations]

Glad you enjoyed it!

[@evev7158]

Very informative illustration! To add a bit more info and a question with it: you can see that the bottom plate which blocks off the bypass is spring loaded and is actually contacting the thermostat housing before the thermostat itself is fully open. So basically the bypass is closed off first, then the thermostat continues to open further and that is facilitated by the fact that the lower plate is able to slide on the thermostat axle/spindle whilst spring loaded and thus pushing against the bypass opening. My questions would be: What is the distance the thermostat must open before the bypass is blocked off? What is the TOTAL distance the thermostat is able to open? At what coolant temperature does the first condition occur (i.e. when bypass is fully closed and all coolant goes into radiator)?

[@williamparry9314]

Cool vid.

[@lukeevans9698]

Thanks!

[@BritannicaRestorations]

No problem!

[@garrydavis3475]

Grand job

[@stefanmazur3238]

Nice demo mike. Top guy. Good video

[@BritannicaRestorations]

Glad you enjoyed it

[@srehmat5598]

Good experiment..

[@BritannicaRestorations]

Thank you! Cheers!

[@weaton25]

I always thought that thermostats just opened when the water got hot did not now that on some engines they redirect the flow of the water.

[@DRUMBAUN]

I liked that.👍

[@47606odin]

Well if it doesn’t close it will overheat, as it will continue to recirculate. what thermostat is fitted in the overheating TDI and it shows you mustn’t drive without a thermostat

[@BritannicaRestorations]

Indeed!

[@sheepdogman1]

Excellent again Mike

[@stu2667]

I once did this for an apprentice because he couldn't understand how a thermastate worked.

[@69woodburner]

Smashing experiment, surprised it worked as it should.

[@BritannicaRestorations]

Me too judging by all the silicone used!

[@clintdouble-u9564]

Brilliant :) Thanks

[@BritannicaRestorations]

You're welcome!

[@richards091]

I enjoyed that.

[@grahamlamb2393]

Fantastic

[@BritannicaRestorations]

Thank you! Cheers!

[@harveysmith100]

My live has been down hill for a while, that was just a push

[@grahameroberts8109]

Time to patent that Mike.

[@BritannicaRestorations]

What colour? lol!

[@grahameroberts8109]

Britannica Restorations Ltd Numeric?

[@scorpionrgp]

Hmm that's got me thinking if it's the same for the 200tdi as well

[@BritannicaRestorations]

yes it is

[@scorpionrgp]

@@BritannicaRestorations I thought so, going to pull my thermostat out my 200 and check it has the "flap" feeling I've been sold the wrong one

[@BritannicaRestorations]

Easy done as the old 2.5 NA fits exactly the same - but no valve

[@melvynrogers3149]

You seem to be the only person on you tube doing these cutaway observations ..be good to see some more..ps now lots of diesels kick out a blast of black smoke on start up..but why does this happen..and can it be stopped...keep up the good work Mike.

[@BritannicaRestorations]

The puff of smoke is the cold start in the injectors - they are like 2 stage - slow crank = excess fuel and once started they put out higher pressure so no smoke Nothing can be done about it

[@melvynrogers3149]

@@BritannicaRestorations ah so that's that mystery solved..cheers.

[@lenhornsey2175]

@@BritannicaRestorations Thanks for solving that mystery ..... it's a good "tool" to use if someone has just pissed you off and is walking past the exhaust .....😉😁

[@Djehuti777]

Excellent video as well. I live in a tropical country. The mechanic advised me to remove thermostat as it is more useful in cold countries. Can you share you thoughts on this?

[@BritannicaRestorations]

Nope - it makes the engine run hotter as the bypass is not closed off

[@BritannicaRestorations]

NEW! My own Subscription/Donation service at affordable rates! britrest.com/subscriptions/ Special tools, stickers and old stock parts! www.britrest.com/shop www.paypal.me/britrest2018

[@ralphdadge302]

interesting experiment, Can you do similar for a defender spec 200Tdi.

[@BritannicaRestorations]

I suppose so - no 200Tdi here

[@jamescunliffe9872]

A window covering the hole so it can be filled with water to simulate operating temperature and sealing face?

[@BritannicaRestorations]

Oh now you are asking for real tricky stuff!

[@jamescunliffe9872]

@@BritannicaRestorations Lol yes I probably am,heat gun for demonstrating on a part that's being scrapped but thinking hot water might be kinder to the wax in the thermostat?

[@BritannicaRestorations]

I don't think I will be using this one again!

[@ianwright40]

Did you check to see if the heater core was blocked... I may have missed that bit... Or maybe you are looking forward to another bath.

[@BritannicaRestorations]

I just did a similar reply - I think there has been a history with this motor and lots of rad seal been used - why was there only a trickle out of the steel heater pipe return, but pressure on the other side ( only 5 PSI)? This may explain why there was a new radiator fitted and the dealer gave him an new head gasket as a 'spare' only to have a cracked head a month after the sale?

[@paddy696]

Mike the corrosion pitting on both faces of Thermostat housing, is that due to no anti freeze or incorrect coolant mix? I'd think Ghana they'd not be adding correct mix there more corrosion! Friend used to service SCANIA, the operators penny pinched just used water to top up if overheating, the "thinwall liners" occassionally rusted through causing Mega engine problems expense!

[@BritannicaRestorations]

Not a drop of anti corrosion - just nasty water

[@kavishruwanpura7213]

Hey sir would like to know if you'd do a 300tdi to puma dashboard conversion video cause it would really help some of us.

[@BritannicaRestorations]

Puma! Lol! We hardly have any Td5 here - may have to wait a few decades..

[@Mikeaubert]

Does the 200Tdi also close the bypass..? I was under the impression that the bypass remained open even when the thermostat opened but it was restricted.?

[@BritannicaRestorations]

It is the same thermostat but without the rubber seal

[@royblackburn1163]

The old fashioned bellows type thermostat used to fail closed, but the wax filled type we all use now are supposed to fail open so overheating because of a thermostat fail should not really happen if anything it should run cool / cold, but in the real world ?

[@BritannicaRestorations]

Seen many a Waxstat fail closed

[@royblackburn1163]

@@BritannicaRestorationsI knew you would say that, just knew it ha ha great vids Mike.

[@nickboylen6873]

Amazing how much bigger things get when they’re hot, and how much smaller they get when cold...😜

[@BritannicaRestorations]

lol!

[@terryatkinson3182]

When it gets hot and bothered, it's lipstick comes out haha

[@michaelevans5953]

Bloody Yorkshire men. Nothing but hot air.............................................................. [from a Lincolnshire man]

[@BritannicaRestorations]

Lol!

[@lenhornsey2175]

No wonder you have unruly hair .... just look at what your hair dryer can do 😲😲

[@BritannicaRestorations]

Lol!