1Y coolant pipes/system

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BarnyE
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1Y coolant pipes/system

Post by BarnyE »

Hi all, my van has had a 1Y engine swap in the past. Whoever swapped it seemed to have ran out of enthusiasm once the got to the coolant system and threw in anything they could get their hands on, with the expansion tank sitting above the engine bay!
So I’m trying to sort it out, this is what I’m left with, an expansion tank which I don’t think is from the t25, maybe?
And some cut pipes. What have people used with this conversion? The donor pipes fit strait to the standard expansion tank? What do I need to order to get it plumbed up?

The rad/heater matrix pipes are all fine, it’s just the expansion tank.

Many thanks.
Barny
Last edited by BarnyE on 31 Mar 2025, 18:18, edited 1 time in total.

BarnyE
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Re: 1Y coolant pipes/system

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colinthefox
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Re: 1Y coolant pipes/system

Post by colinthefox »

Hmmm. Quite a lot going on here.

Here's a photo of the engine bay on my AEF conversion, which would be pretty similar to a 1Y installation.Image
 Some things to note in this photo........
All the hoses, expansion tank, etc are from the original 1.6CS installation, as the 1 Y and AEF are virtually bolt-in replacements, with the same layout of hose connections. However, it looks like yours was originally a petrol engine, so everything is completely different. I think what you should do is to have a good look at an original 1.6NA diesel installation, try to get all the hoses brackets and expansion tank, overflow bottle, and make your installation look like that.

Some other points are....
  • It's difficult to see, but it looks like your sump is the 1Y sump, when it should be from the 1.6 diesel, including the dipstick. That probably means that the oil pickup in the sump is from the 1Y engine, which is not right for the 50degree lean in the T25
  • You are missing a clip off the number 3/4 pair of injection pipes. These clips don't look much, but are important to stop the pipes fracturing due to vibrations
  • Your incoming fuel pipe is badly routed within flailing distance of the auxiliary belt.
  • The battery looks like it is still at the front. Diesels had a bigger battery at the rear, because it's a long way to take a heavy diesel starting current through the main cable.
  • All sorts of cables, pipes etc are not supported, including the front-to-back pipes, which should be up in the circular recesses a few inches above them, and the main alternator cable has no support.
  • The bypass hose (the big one coming from the cylinder head) isn't connected to anything, (and the cooling pipework generally isn't a workable system. You may have disconnected stuff for the photo though.

You would be welcome to have a look at my installation (I'm in Somerset), if you want. If not then I recommend finding someone with an original 1.6 NA diesel to visit. I'm afraid you have quite a bit of work to do to get yourself a working and reliable installation.
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The Hairy Camper
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Re: 1Y coolant pipes/system

Post by The Hairy Camper »

As Colin has mentioned, there is a lot more missing than just coolant pipes. I will try and take a picture of my diesel setup tomorrow to give you an idea of what's missing.

I cannot see an air box or actual coolant pipes (just hoses). If the original 1Y sump and oil pump are still being used too then that's not going to be a reliable runner due to oil starvation.

Best bet would be to find someone breaking a diesel T3 to grab some parts.
1984 Autosleeper, pop-top, 1.9 1Y, 5-Speed

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Rik
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Re: 1Y coolant pipes/system

Post by Rik »

I still have my original CS. Can send you some photos of the engine bay if it would help?
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The Hairy Camper
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Re: 1Y coolant pipes/system

Post by The Hairy Camper »

Here are some pictures of my Diesel engine bay.Image
Image
Image
You can see the long metal (sometimes yellow plastic) coolant pipes in this photo. From what I can see, your pipes are missing.

Hope this helps.
1984 Autosleeper, pop-top, 1.9 1Y, 5-Speed

colinthefox
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Re: 1Y coolant pipes/system

Post by colinthefox »

The Hairy Camper wrote: 07 Apr 2025, 18:31 Here are some pictures of my Diesel engine bay.

You can see the long metal (sometimes yellow plastic) coolant pipes in this photo. From what I can see, your pipes are missing.

Hope this helps.
They are there. but sort of dangling several inches below where they should be, and one much closer in to the side of the engine.
 
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The Hairy Camper
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Re: 1Y coolant pipes/system

Post by The Hairy Camper »

colinthefox wrote: 08 Apr 2025, 21:19
The Hairy Camper wrote: 07 Apr 2025, 18:31 Here are some pictures of my Diesel engine bay.

You can see the long metal (sometimes yellow plastic) coolant pipes in this photo. From what I can see, your pipes are missing.

Hope this helps.
They are there. but sort of dangling several inches below where they should be, and one much closer in to the side of the engine.
 

I think I can see one of the pipes now. That can't be good if they aren't supported properly.
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BarnyE
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Re: 1Y coolant pipes/system

Post by BarnyE »

Hi all, thanks for the responses. I’ve been chatting to brickwerks and have a fair few bits on order, new front to back hoses, all new hoses for the engine. Battery tray, expansion tanks, the lot.
I was aware there was quite a lot of work to do here, so happy to keep plodding along.

I see there’s a little wire clip that holds the front to rear pipes up in the bulkhead. Any ideas where I may be able to source one?

Thanks for letting me know about the sump. That’s one thing I wasn’t aware of. I’ll investigate that. It does have a dip stick which has been “re-notched” to show oil level.

There’s been plenty of bodge jobs, so I’m not surprised.

Currently has no air intake or filter as I removed the set up that was on it - again a complete bodge. Will replace with the correct stuff.
I’ll change all the fuel lines and filter to the correct set up.

I’ll take some pictures tomorrow of the sump so you can confirm what I have.
The battery was at the back, but the battery tray chopped out and it was. Pushed into the “air box” ?? Don’t know what it’s called. As I said it was very botched, but I’m making it better!! You can ignore the electrics, again, lots of twisted wires and electrical tape 🤦🏼‍♂️ that’s another job I’ll fix before it goes anywhere near the road.

Luckily whoever don’t the engine swap hasn’t been near the rest of the van, it’s all very original and unmolested!


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BarnyE
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Re: 1Y coolant pipes/system

Post by BarnyE »

So I’m pretty sure the sump is the correct one. I asked the guy I bought it off, he said he did change it. But I’ve got a clearer picture anyway.
Also what’s this coming from the corner of the sump?Image
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colinthefox
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Re: 1Y coolant pipes/system

Post by colinthefox »

That's the correct sump then. Sorry I raised unnecessary concerns. The original diesel setup has an oil filling tube accessible via the "cat flap", but this would clash with the auxiliary belt, so they have made up something. It's simple enough to fill the oil through the cap on the cam cover, so you could just remove this and blank off the flange on the sump with a small diamond shaped blank plate.
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colinthefox
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Re: 1Y coolant pipes/system

Post by colinthefox »

As for the little wire clips, you could just use a couple of fat zip ties in place of them.
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BarnyE
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Re: 1Y coolant pipes/system

Post by BarnyE »

Begining to look something like it now.Image


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colinthefox
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Re: 1Y coolant pipes/system

Post by colinthefox »

Well done, that's serious progress. You have worm drive clips on the fuel pipes though. These should be changed to proper fuel hose clips, as the ones you have may distort the small diameter hoses and can introduce air leaks into the fuel system. Once the system is sucking in air, even in small amounts you may have difficulties starting, and rough running. Now you're doing all this work, you might as well use the correct clips.
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BarnyE
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Re: 1Y coolant pipes/system

Post by BarnyE »

I’ll have a look for the correct clips. Don’t mean the spring type ones?

Next question…
I’ve fitted the inlet manifold and airbox, to replace the previous bodged intake. However, the round breather that sits on the rocker cover is really pushed against the airbox. Not really fitting in properly. I’m assuming, again, there’s a way to do this that it all fits nicely?Image
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