The Brick-yard Homepage Brickwerks
Forum Home Forum Home > T3 Section > T3 Diesel upgrades
  New Posts New Posts RSS Feed - AAZ overheating issues...
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

AAZ overheating issues...

 Post Reply Post Reply
Author
Message
Steve o View Drop Down
Groupie
Groupie
Avatar

Joined: 19 Jul 11
Location: Bristol
Status: Offline
Points: 43
Post Options Post Options   Thanks (0) Thanks(0)   Quote Steve o Quote  Post ReplyReply Direct Link To This Post Topic: AAZ overheating issues...
    Posted: 14 Aug 11 at 12:22
Bought a van already converted to an AAZ engine, runs ok but the expansion tank is fitted to the right hand side of the engine. Had a garage look at it and they have linked another expansion tank which is located above the engine bay. Apparently because it's gravity fed, has anyone else had any issues in relation to overheating or locating the expansion rank so I can close the engine lid !!!

Never had an engine conversion before so bear with me and my poor explanation ...
Back to Top
timmythedog View Drop Down
Vanorak
Vanorak

westy fetishist

Joined: 29 May 08
Location: Nr Grenoble
Status: Offline
Points: 2984
Post Options Post Options   Thanks (0) Thanks(0)   Quote timmythedog Quote  Post ReplyReply Direct Link To This Post Posted: 14 Aug 11 at 15:01
photographic evidence will help.Smile
89 lhd Exclusive minibus 2.1dj




Caravelle GL AFN tdi(I loved it, but it's gone)

53 plate T4 Panel. 888 special x factor.



Back to Top
H-G View Drop Down
Groupie
Groupie


Joined: 18 Sep 09
Status: Offline
Points: 61
Post Options Post Options   Thanks (0) Thanks(0)   Quote H-G Quote  Post ReplyReply Direct Link To This Post Posted: 14 Aug 11 at 16:00
I thought that they were vacuum fed?  My expansion tank is exactly where the it was for the JX and no problems at all.  

I fitted the cooler thermostat, chemical flushed the system and an oil cooler when I did my conversion.  It now runs cooler than the JX did, even on the long climbs.

Worth checking the blue 'dalek' cap on the main water bottle and than the hose for there to the expansion tank is a tight fit.  MAy also be worth checking that the thermostat is opening as it should and also that the whole system has been filled and bled properly. If you only have a half-full rad then it's going to struggle to cool things down at the back.  I would highly recommend an oil cooler - not the cheapest item to buy, but easy to fit and a damn sight cheaper than a replacement engine.


Back to Top
rolo View Drop Down
Yardie
Yardie
Avatar

Joined: 17 Oct 08
Location: burnley
Status: Offline
Points: 515
Post Options Post Options   Thanks (0) Thanks(0)   Quote rolo Quote  Post ReplyReply Direct Link To This Post Posted: 17 Aug 11 at 06:30
Expansion tank should be behind no. plate at about same height as header tank, once at right level, is fed and diminished by pressure and suction from the main tank and regulated by the cap on the header tank.
Possibly the air filter has been moved to the right air duct by piping across the original site, if not put it where it should be; if so, a smaller, bottom connected, top filled, non pressured expansion can be fitted on n/s of engine bay
the last one
Back to Top
funkyweasel View Drop Down
Not Quite Newbie
Not Quite Newbie
Avatar

Joined: 23 May 13
Location: Suffolk
Status: Offline
Points: 11
Post Options Post Options   Thanks (0) Thanks(0)   Quote funkyweasel Quote  Post ReplyReply Direct Link To This Post Posted: 18 Jul 13 at 19:46

Apologies for opening up what looks to be an old thread, but I really want to get to the bottom of these cooling AAZ issues.

I have just completed my AAZ conversion using my own tried and trusted 1996 golf donor AAZ.

I know it has been hot of late (26°C+) but I am still getting 108° at 60MPH on the motorway.

If I back off to 50MPH it goes down to 95°C. Idling it will go down even lower (88°C)

 

What I’ve tried:

- Completely flushed system with degreaser rad flush (multiple hot flushings)

- I have installed a brand new EIS (German built) radiator.

-Have installed a 235mm 25 row Mocal oil cooler with 5/8 inch pipe and high flow thermostatic (80°C) take-off sandwich (also Mocal).

-Installed brand new water pump (installed into golf about 2 months before conversion).

-Installed lower opening 82°C thermostat.

 

Other info.

-I am 100% sure I have bled the system well. I have nothing but coolant coming out of rad bleeder  when running hot.

- I am using 10 litres of coolant to 6 litres of water (so that is 62% coolant, the pink variety).

-I am not loosing coolant and I believe my expansion cap (black one from the original CS engine) is working fine.

-I have measured the temperature with two sensors/gauges… one is a digital meter that I confirmed is ok with a kitchen boiling water test.

- I have recently replaced the radiator fan switch and I have heard the rad fan come on once or twice, when I was bleeding the system.

- The oil cooler has made a big difference to the sump temper (as felt by hand) and the oil cooler itself feels nice and very hot so it must have made some improvement, but I can honestly say I did not see much difference in the water temperature.

 I am now thinking that I am not getting the water flow required to achieve what the original golf did so well with its short set of radiator pipes (and two fan units)

 Questions:

-Has anyone attempted using a coolant circulation pump (e.g. V51 or 0392020039  or VW 078965561) to increase the flow to the radiator?

 - Has anyone replaced the 2 stage fan switch with a switch that brings the fan on at a lower temperature(s)?

 - Is 110°C a concern at 60MPH? I suspect if a hill and a trailer load of camping stuff were involved it would continue to rise.

So frustrating. 

Back to Top
syncronized View Drop Down
Not Quite Newbie
Not Quite Newbie


Joined: 28 Apr 13
Status: Offline
Points: 25
Post Options Post Options   Thanks (0) Thanks(0)   Quote syncronized Quote  Post ReplyReply Direct Link To This Post Posted: 18 Jul 13 at 23:34
I replaced the blue antifreeze in all my vehicles last year with the new pink variety (50%) & all of them run a good few degrees hotter now. I'm going to change back to the usual blue type in the VW & see if the temp drops back to its old levels. You say you are running 62% antifreeze, maybe that would exacerbate the problem, as I thought 40 to 50% was optimum before the heat transfer properties of the coolant was reduced?
Back to Top
Allanw View Drop Down
Vanorak
Vanorak
Avatar
SYCOPHANTIC TRAINEE WELSHMAN

Joined: 21 Mar 10
Location: New Zealand
Status: Offline
Points: 1207
Post Options Post Options   Thanks (0) Thanks(0)   Quote Allanw Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 06:23
Coolant isn't as good as cooling as water is - too muchg can slow down the heat transfer. It can also be a bit viscous.

I don't think that would get you up to 108C though!

You could try straight water just to see, but I don't think it'd be that.
Allan :-)

'84 T3 Kombi, EJ25 DOHC, apprentice Viking...

Duct Tape can't fix stupid, but it can MUFFLE the sound.
Back to Top
funkyweasel View Drop Down
Not Quite Newbie
Not Quite Newbie
Avatar

Joined: 23 May 13
Location: Suffolk
Status: Offline
Points: 11
Post Options Post Options   Thanks (0) Thanks(0)   Quote funkyweasel Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 08:47

Thanks guys for your coolant comments. I may reduce the ratio, but I think I have found my problem:

I put two temp indicator lights on my dash and ran lines to the two output fan feeds from the dual speed thermostatic switch in the radiator, went for a drive and push the van hard on a hot day and found that the temperature was 110°C and the fans hadn't yet turned on.

 

I have just check my radiator switch and I have the 191 959 481C version which has higher temperature ON value then what I need (i.e: 95-84C, 102-91C).

 

I will get the 251-959-481/K version (87-76/93-82C) and that has gotta be better for the whole system.

http://www.status-vw.co.uk/251-959-481-k-dual-thermo-switch-for-vw-T3-and-vw-t4-1984-1993.html

 

Finally some progress.

 
 
Back to Top
light View Drop Down
Vanorak
Vanorak


Joined: 25 May 10
Status: Offline
Points: 1070
Post Options Post Options   Thanks (0) Thanks(0)   Quote light Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 16:20
Originally posted by funkyweasel funkyweasel wrote:

Thanks guys for your coolant comments. I may reduce the ratio, but I think I have found my problem:

I put two temp indicator lights on my dash and ran lines to the two output fan feeds from the dual speed thermostatic switch in the radiator, went for a drive and push the van hard on a hot day and found that the temperature was 110°C and the fans hadn't yet turned on.

 

I have just check my radiator switch and I have the 191 959 481C version which has higher temperature ON value then what I need (i.e: 95-84C, 102-91C).

 

I will get the 251-959-481/K version (87-76/93-82C) and that has gotta be better for the whole system.

http://www.status-vw.co.uk/251-959-481-k-dual-thermo-switch-for-vw-T3-and-vw-t4-1984-1993.html

 

Finally some progress.

 
 
Just a thought
 
What alternator set up have you used ?
 
I have seen a few aaz/1y conversions that have used the 1y/aaz alternator/water pump serpentine belt setup in their t3`s but have routed the belt wrong resulting in the water pump running backwards  ,the cooling system works around town but don't do the job at motorway speeds
Back to Top
funkyweasel View Drop Down
Not Quite Newbie
Not Quite Newbie
Avatar

Joined: 23 May 13
Location: Suffolk
Status: Offline
Points: 11
Post Options Post Options   Thanks (0) Thanks(0)   Quote funkyweasel Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 18:46
My GOD!! Thanks so much for that little gem, you really may have saved next week's camper holiday.
I looks like the muppet who replaced my Golfs water pump has incorrectly routed the alternator belt (before the conversion took place).
I have checked with ElsaWin and it looks like the 1996 AAZ has a CCW rotating water pump. My AAZ is currently rotating in the oposite direction as the crank.
 
I can't see any markings for the direction of rotation on the water pump. Can anyone confirm that ALL AAZ water pumps should rotate the same way (i.e CCW)?
 
Thanks again for your post.
 
 
 
Back to Top
funkyweasel View Drop Down
Not Quite Newbie
Not Quite Newbie
Avatar

Joined: 23 May 13
Location: Suffolk
Status: Offline
Points: 11
Post Options Post Options   Thanks (0) Thanks(0)   Quote funkyweasel Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 19:41

Actually it looks like the crank rotates CW and according to ElsaWin and an RAC friend of mine the belt should go around the bottom of the water pump (confirming that both crank, water pump and alternator should rotate in the same direction).

 

Having said all that, could someone please check their AAZ and tell me if the above is correct?

Thanks.

 
Back to Top
H-G View Drop Down
Groupie
Groupie


Joined: 18 Sep 09
Status: Offline
Points: 61
Post Options Post Options   Thanks (0) Thanks(0)   Quote H-G Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 19:45
https://www.google.co.uk/search?q=vw+aaz+cambelt+route&client=safari&hl=en&source=lnms&tbm=isch&sa=X&ei=ByzsUcrnLK3X7Aai5YHYDA&ved=0CAkQ_AUoAA&biw=1024&bih=672#biv=i%7C0%3Bd%7CMn4iHK9BM2GNQM%3A
Back to Top
funkyweasel View Drop Down
Not Quite Newbie
Not Quite Newbie
Avatar

Joined: 23 May 13
Location: Suffolk
Status: Offline
Points: 11
Post Options Post Options   Thanks (0) Thanks(0)   Quote funkyweasel Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 13 at 20:25

Success! Smile.

Thanks to those who posted ideas. Espeshlly "light" for putting me on the right track. Just swapped the belt direction around the water pump pully and now I am running cool as a cucumber. Really pushed it to 70MH and could only just get it to 96°C.

 

So glad I didn't go down the auxillary pump route to solve this. 

Just to confirm, my ribbed alternator belt goes around the outside of all three pulleys. I have a 1996 AAZ from a Golf CL.

Cheers.
Back to Top
evantis121 View Drop Down
Newbie
Newbie


Joined: 08 Jul 14
Location: United Kingdom
Status: Offline
Points: 1
Post Options Post Options   Thanks (0) Thanks(0)   Quote evantis121 Quote  Post ReplyReply Direct Link To This Post Posted: 08 Jul 14 at 16:17
Hi Funkyweasel, I've also got a hot running AAZ issue. The needle goes to 2/3 at idle and 3/4 if theres a hill involved. I'm just wondering if it could be the water pump. I'm a bit confused by the posts above though. should it rotate CW or CCW ?? Thanks
Back to Top
Twffr View Drop Down
Newbie
Newbie


Joined: 15 Dec 11
Location: Wrexham
Status: Offline
Points: 2
Post Options Post Options   Thanks (0) Thanks(0)   Quote Twffr Quote  Post ReplyReply Direct Link To This Post Posted: 13 Jul 14 at 12:40
Originally posted by evantis121 evantis121 wrote:

Hi Funkyweasel, I've also got a hot running AAZ issue. The needle goes to 2/3 at idle and 3/4 if theres a hill involved. I'm just wondering if it could be the water pump. I'm a bit confused by the posts above though. should it rotate CW or CCW ?? Thanks

In this thread the narrow 'V' belt would run under the water pump pulley and the wide flat+ribbed belt should run over the top the water pump pulley. The latter runs in the opposite direction to the former so they are different internally. The problem arose because the ribbed belt was put on in the same way as a V belt would and drove the pump backwards and so less efficiently.

What type of belt does your AAZ have?
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down


The WebThis site