When putting a Subaru EJ Series engine in the rear of a VW, the standard coolant manifold points the radiator top hose towards the left hand rear light. This is pretty much exactly opposite where it needs to point to join to the VW coolant pipes in any water cooled T25 / T3 / Vanagon. Although the bolt pattern where the manifold bolts to the top of the block is symmetrical, no standard manifolds fit backwards because they hit the block near the starter motor. A reversed coolant manifold is the solution to this, making the plumbing very much simpler and neater in almost* any VW model which has the radiator mounted forwards of the engine.
Not every design of Subaru coolant manifold can be modified to fit in reverse. See below for more details on which can and which can’t. Also, certain engines (in particular post MY97 turbos and those with EGR) require a reversed manifold from a different models, or require the manifold to be modified slightly differently if the engine has certain features (such as the tumbler valves on some turbo models). There is more info on this towards the bottom of this page, but if you are unsure which reversed manifold type your turbo or normally aspirated model with EGR needs, please ask before sourcing one – this can get very confusing.
* the only exception is the late bay / T2b. These have an extra chassis crossmember below the rear edge of the fuel tank which is not there in any other model, which gets in the way of fitting a reversed coolant manifold.
Reversal of your own coolant manifold (part no. 125-00001):
Price: £58.33 GBP +VAT (£70.00)
Reversal of your own coolant manifold. Includes re-machining of the o-ring faces when required (it is on around 60% of manifolds), weld repair of any crevice corrosion as long as it hasn’t corroded right through (it almost never has), and new o-rings.
Any other repairs such as replacing the 8mm steel pipe which feeds the preheat coolant to the throttle body if it is damaged or badly corroded costs extra.
See below for which types of manifold we can and can’t modify to fit in reverse (shown before being modified).
This is not an exchange manifold service. We tried doing them on an exchange basis, but there is no way that it can keep everybody happy, even with a surcharge. Too many times the customer either:
- Sent their manifold back in exchange a year or more later – that is of no use to us
- Never sent their manifold back – that is of no use to us
- Was unhappy if we returned a perfectly functional manifold that was not as clean or had more (aesthetic, not function affecting) corrosion than the one they sent us
The best solution to all of the above is to reverse the customers own manifold. That way we’re not left with less manifolds, and they’re always happy with the condition. We usually save manifolds up and reverse them every one to two weeks as required. We can turn them around faster if required for no extra cost, but only of you arrange that up front.
Reversed coolant manifold outright purchase (sorry, customers outside the UK only) (part no. 800-00048)
Price £87.50 GBP +VAT (£105.00)
No need to send your manifold to us. Sorry, only available to customers outside the UK (unless we find an infinite source of OK condition used manifolds for sensible prices). For customers who are abroad, shipping your manifold to us will often cost about as much as the manifold is worth, so obviously doesn’t make sense (unless you were about to pay the insane price one US supplier charges to reverse coolant manifolds). Any spare coolant manifolds we get, we keep for customers in your situation.
Which coolant manifold types can be modified to fit in reverse ?:
These types can be modified to fit in reverse:
There are many other types of coolant manifolds than the ones shown above (easily more than 10 others). None of them are practical to reverse (many of them are shown at the bottom of the page), but many of them can be replaced by these types once they are reversed.
If you have coolant manifolds which you don’t need, we pay from £15 to £45 for them depending on condition, as long as we don’t have too many at the time).
These reversed manifolds fit all normally aspirated engines from MY90 to MY01, and all turbo engines from MY90 to around MY96. With later models than that a reversed manifold can be fitted, but it often needs to be based on a different manifold design to the one which was originally on the engine:
- If your engine is one of the normally aspirated EJ series models with EGR, your reversed manifold needs to be type D or E as shown above (very preferably type E)
- If your engine is turbo and later than around MY96, your reversed manifold needs to be type D or E as shown above (very preferably type E)
- If your engine is turbo and has tumbler valves, we need to know this when reversing it, as they’re done differently to these engines
Please note, this does not include reversing manifolds which have been painted. If you have one which is painted, please either remove all paint from it before sending, or we can blast it at extra cost (£15). It’ll be blasted with aluminium oxide, which doesn’t leave the nicest finish on aluminium though (it’s rough – about like 280 grit sandpaper. Maybe ideal if you’re painting it again, but otherwise not the nicest finish)
These manifold types we can’t me modify to fit in reverse: (all use the 30mm bolts) :
See Coolant Plumbing Schematic – Subaru EJ Series Engine in a Rear Engined VW
See Coolant Filling and Bleeding Procedure for details of how to fill the system that these reversed manifolds are designed for with coolant
See Cooling a Subaru Engine in a VW for a lot of general information, including important info on why you need to choose VW coolant header tank caps very carefully, and why you should only ever use genuine Subaru thermostats.