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  Topic Review (Newest First)
4-5-19 21:29
Mazda R 2 diesel in Asia Rocsta

I have a ping which sounds like a diesel ping when I speed up at about 70km .
I rechecked my injector pump and I found 2 marks on pully. A 1 and also next a + mark.
Which is the correct mark. It is a NA engine. It also lacks power . Battle to get to 90km And ping go slightly away if I ease of accelerator.
I just bought it and guy has just fitted a new head and injectors.
2-4-19 9:14
Originally Posted by Imonlyhuman View Post
Anyone still active on this thread?

Im from Sri Lanka and I own a Mazda Bongo van with a NA RF engine
2-14-17 22:14
Imonlyhuman Anyone still active on this thread?
1-19-15 8:30
Stuski just wanted to say this is a great threat, recently bought a 4th gen B series ute/94 ford courier with an R2 engine and was having a hell of a time finding much info but after reading this threat i now feel more familiar with my own engine

have had some fun with fixing problems caused by at least 1 previous owner with the electrics for the rear/dash lights being fried and hacked apart

after finding various bits here and there on the tail end I've come to the conclusion someone jack knifed a trailer pinching the tail lights wiring then put over rated fuses in till they burnt stuff out. have since properly replaced/patched most of the damaged wiring in the dash and running to the tail lights, only electrical issue left is the reverse lights still don't come on, think its the sensor/switch in the gear box has failed but have yet to trace it

second issue was the radiator appears to have had something dropped on its outlet pipe causing cracking around it so i have re soldered it and now the temp hardly passes the 'cold' point on the gauge under normal driving conditions instead of sitting in the middle and slowly eating water (50km drive would need another 2L of water put in)

while i had the engine partially apart for the radiator repair i also took the bus bar off the glow plugs and measured their resistance which was 1-1.5 Ohms each drawing a total of about 750w (from memory)

the battery is at least 10 years old and very much on its last legs,seems to have at least one weak/dead cell which makes it a pain to start on cold mornings or after short trips so will be getting a new one soon

also a past owner put a racing steering wheel on a utility truck that has no power steering and a tare weight of over 1 metric ton and over sized rear wheel rims and lower profile tyres yet front are stock as a rock which makes replacing tyres a painfully expensive exercise
8-1-14 8:25
zaib75 Don't have compression tester but will try to find it on any workshop
Engine doesn't reduce a single drop of oil even after 5k km and no loss in power too
8-1-14 4:16
chief tool A little bit of blow by is normal along with some oil migration.

If it worries you, do a compression check. Not sure what the limit is for an R2 but 384psi is the lower limit on an RF.

If the compression is low - yes rings will need to be changed & the bore honed at least. It depends on how worn the bores are as to whether you would get away with just a hone or a re bore.
R2 motors come as two types; some blocks are cast as one piece and some have replaceable cylinder liners. The former would need to be bored out to the next oversize and the pistons replaced. The latter would just need new liners pressed in.

The advantage of replaceable cylinder liners is that you don't need to replace pistons due to oversized bore
7-31-14 16:04
zaib75 Eid Mubarak (best wishes for the best holy day)

Today I replaced engine oil pan with original B2200 ones and hope it will not leak again.
But I saw some oil drops near intake manifold where rubber intake hose meets with metal pipe which is attached to intake manifold with 2 bolts .
removed it and oh there's more oil.
I fixed it back applying silicone sealant to stop oil seepage but what to do now?
Is it blow by and if so how to tackle?
Compression check? Valve seals check or piston rings change?
7-21-14 4:58
chief tool I would leave the R2 head on the R2 block, why swap a head which is essentially the same unless there is a problem with the one that is on there now. Save your RF-T head as a spare and just swap the turbo, manifolds & IP if you have the RF-T IP.

The only thing to be wary of; the R2 block is about an inch taller than the RF, so anything from the turbo that connects to the block might need to be modified a little.
7-20-14 19:08
zaib75 So will it be a successful swap rf-t head+turbo stuff on r2 ?
7-20-14 18:28
chief tool The pistons are different & so is the IP. The head & injectors are the same. The engines are so over engineered that the NA engine is fine to be lightly boosted. The head is the limiting factor in any case.

I would not worry, I would just bolt the turbo manifolds onto the R2. Boost control is via the internal wastegate. On a diesel though boost is really controlled by fuel, the wastegate is just there for protection for over boost.

The turbo injector pump has an aneroid chamber which is connected to the turbo outlet so it senses when the turbo is boosting and increases the stroke to inject more fuel.

However, when the aftermarket turbos are fitted, the tuners simply increase the governor fuel amount & maximum fuel amount. It works, the downside is that if you floor it before the turbo is on boost you get a black smoke dump. If you ease onto the power it its not so bad.

With the turbo IP, the aneroid allows the engine to come onto boost before adding the extra fuel. This is also why the wastegate is needed. More fuel would keep building more boost which then increases the fuel until the wastegate opens.

Using the NA pump, the fuel has a set limit, so no wastegate is needed.
7-20-14 14:04
zaib75 I have limited knowledge about turbo charging and boost control etc
I heared that turbo piston are different from NA engine pistons and pump ,injectors
i have plan to swap mazda rf head and all turbo stuff , is it compatible with R2
7-20-14 14:00
zaib75 Both engine foundations cracked and stupid mechanic didnt paid attention and cut the lower sump side which was touching support metal bar under that sump and welded it again
Now its 4 month with leaking oil pan but this time i poured 2 liter oil which was leaked
7-20-14 9:44
chief tool The FWD & RWD sumps are different, but as far as I know between RF & R2 RWD they are the same.
I've not heard of a leaking sump before except through the use of cork gaskets. The sump itself never goes wrong.
Someone used a cork gasket on my car before I bought it, there was oil leaking out everywhere. I used sealant like the WSM recommends and it has not leaked a drop since.

As for turbocharging. I've known quite a few people who have successfully turbocharged the NA motor. I know the factory turbo has slightly lower compression (20.9:1) and larger small end bearings, but this does not seem to make any difference reliability wise.

Under 20psi they seem to hold up. I planned to stay to 15-17 for reliability. factory boost is 10-12psi. I've heard of people lifting the head over 20psi.

There were aftermarket turbo kits sold for the R2 in this country.

Don't forget that Mazda still use the same conrods from the early RF-T on the most recent 2.0 RF turbo Common rail motor making 360nm. I'd say they are well over designed. The NA rods should be fine for a lightly boosted R2.
7-20-14 7:14
zaib75 Hello Chief
Do Mazda RF and R2 share same oil chamber (sump) because my engine chamber is leaked and I'm searching and a friend have RF will it direct fit without any alteration
And what you say about turbo charging a NA engine what parts I have to change like con.rod or head? And is it reliable to fit a turbo on R2
7-11-14 18:43
chief tool
Originally Posted by zaib75 View Post
If I'm not wrong you can replace valve seals without removing head
Replace and enjoy
Yes, this is true. I have the tools and the new stem seals ready to go, just haven't had the time.

I don't see any reason you couldn't use the ND pump.

In the USA FWD versions of the RF (in the 626 and Escort) got the ND pump and here in Australia we got the Diesel Kiki (Zexel) They are interchangeable as far as I am aware.

So long as it physically bolts on it'll probably work.
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