4Y Replace vs Rebuild

[Willied]

A while back we discussed the merits of rebuilding your 4Y rather than replacing it with something else or just dropping in a Fong Kong motor. When I got my Hilux it had a seized 4Y in it and due to time constraints and no knowledge of build quality we dropped a Fong Kong 4Y into the vehicle. In the past 45 000km I have had some issues with the motor of which a couple arose from build and cast quality. An example of this was the head gasket that was replaced due to improperly tightened head bolts and before I had done 15 000km I had the carb rebuilt and later dropped it for a Weber which was recently replaced with EFI to prevent lean/rich conditions traveling from lower to higher altitudes and vice versa.
I have to add that the EFI was the best mod done to my motor and I will do it again any day. The past weekend I travelled to Phalaborwa to take part in the yearly river trip that sees one travel up the Molototsi river for about 60km negotiating coarse sands and rocky outcrops in the river bed.. All in all good fun!

Cutting to the chase, I filled up with dirty fuel along the way that blocked my fuel filter completely. Before cutting of the supply it cause the motor to run in a lean condition under severe strain. This heated the motor past the capabilities of the radiator and the slow driving conditions took its toll in the form of a blown head gasket.

This puts me at a cross roads, rebuild, replace or simply do the gasket if possible. To me the latter is not an option at the moment as the motor is not running at optimal even if the gasket is functioning like it should. So rebuild or replace are the options I will be investigating.

Replace I hear you say.. 4Y keep the 4Y.. Well I kind of like the spunky motor and it’s low down grunt.. Sure all the other motors make more power but I like the way this one just climbs over everything.

Replacement options:
3RZ – 2.7l inline 4, 8 valve version (R15 500)
1MZ – 3.0l V6 (Imported Toyota motor fitted to Australian Camry) (Price to be confirmed)
3GR-FE – 3.0l V6 (Fitted to the Lexus range of Toyota) (R 12 500)
5VZ-FE is not on the list because of a cast iron block and heavy fuel consumption.
1UZ-FE is not an option as I do not have the dosh to fit it or maintain the drivetrain afterwards.
All motors picked for brand and availability, prices exclude ECU.

Parts list:
Head – Toyota original head (Price to be confirmed) or Machining existing head (Price to be confirmed)
Gasket set – As the motor will be stripped bare a new set is a must (Price to be confirmed)
Piston Rings – Sump compression is visible as breather lubricates manifold properly on the inside (Price to be confirmed)
Pistons – Should not be required (Price to be confirmed)
Conrods – Should not be required (Price to be confirmed)
Bearings – Always replace them after you have removed them, its good practice (Price to be confirmed)
Seals – (Price to be confirmed)
Waterpump – It is still functioning but I will have more faith in a Toyota original (Price to be confirmed)
Labour – All work will be done by myself with proper supervision by a qualified technician, I am sure he will m0er me over the fingers more than once in the rebuild. (Priceless)

The build will give me the opportunity to gas flow the head, balance the motor, increase compression and to turn the stock sump the right way around so the diff does not reshape it.

Any suggestions and or inputs will be appreciated and researched.

[LouisZ]

Willie probeer meer uitvind oor die 3GR of selfs die 4GR, kyk net water Aftermarket Ecu jan die VVTi goed kan beheer, lyk na 'n goeie engin. Of anders vergelyk die koste van oorbou teenoor oor om te vervang.

[Willied]

Die koste vergelyking is die belangrike deel waarna ek wil kyk. Het vanaand die motor oopgemaak en kon nie die lek plek op die gasket kry nie, maar sal more in die lig beter kan sien. Het wel opgespoor waarna toe die olie gaan. Silinder een en vier het biedjie 'n drink probleem ontwikkel en dink die hitte het moontlik die ringe sag gemaak.

As ek na die 3GR kyk sal ek verkies om die cam te vervang sodat ek die krag laer af kan skuif al boed ek biedjie daarvoor in. Al kry ek 120kW op die flywheel sal ek meer as gelukkig wees.

[Willied]

'n Biedjie van 'n update. Ek het gisteraand die head afgehaal om te kyk wat binne aangaan. Die lek plek in die gasket is nie baie duidelik nie en die lig was nie baie goed nie, sal vandag alles mooi deur gaan as ek kans het. Hiermee 'n foto van die head en die blok.

Silinder een en vier het so biedjie olie op, sal verduidelik hoekom daar kompressie is in die sump.

[Mr_B]

5VZ-FE is not on the list because of a cast iron block and heavy fuel consumption.

Hi Willied,

Firstly I'm every sorry to hear about your engine troubles, with the fong kongs, sometimes you win, but most of the time you lose! I advice guys that the fong kong sub-assembly is fine, but don't use the ancillaries, rather refit your original Toyota parts, and an original Toyota head gasket and head. Yes, it more time consuming, won't cost more, and you avoid all the fong kong nasty bits. A friend of mine has completed over 100000km with this formula.

The quote above, IMHO the 5VZ is the ultimate SFA conversion, the motor is short, fitting it no issue. The Lexus V8 is too powerful, despite what people will tell you, they break drive train parts... some 4x4 course demand a heavy right foot and that amount of power just breaks stuff. It's probably the best fitting 6 pot engine in a SFA. I spent 4 days driving in Steve's one, solid torque at the bottom, beautiful exhaust note. Best of all, offroad on serious 4x4 tracks in the Namaqua we average 4.8km/l in 4x4, mixed L/H ratio, fully packed. Steve has got as much as 8km/l on the open road at 100-110km/h. The engine is managed by a Dicktator, and runs as sweat and smooth as ever. If I ever own a SFA again, it'll be a difficult choice between the 4L V6(1GR-FE) and 3.4L V6(5VZ). But the 3.4L is just so much more cost effective than the 4L. If you know what you doing this conversion shouldn't cost more than 30K diy.

Mr B

[Willied]

Thanks for the advice Mr B! I have sometime ago had a long hard look at fitting the 5VZ and yes, in the states this was the motor fitted to the SFA clubcab.. A very good match indeed. But, I would like to keep weight down and these motors are of an older generation. If I do upgrade I would prefer one of the MZ or GR gen motors.

Sure the 3GR does not have the torque of the other, but then it has more than the 4Y and with a decent cam it can be made to what I want. Not looking to pull the earth out of orbit on take off, just something stronger and more reliable than a knockoff motor.

Looking at cost it might still be the best to just do a proper rebuild on the 4Y and as soon as the prices come in I can confirm this. My first choice would be the 3RZ, but a good running 4Y is not a bad second place.

[Willied]

Ek het toe van Toyota af die pryse gekry om die internals te vervang.. Kyk so na R 11 000.00 vir alles wat 'n water pomp insluit. As ek net bearings, ringe en water pomp doen draai die rekening so op R 7000.00..

[Mr_B]

My first choice would be the 3RZ, but a good running 4Y is not a bad second place.

That's if there only 2 cars in the race... anymore and the 4Y will always arrive last!


Willied that's not a bad quote, a friend of mine got ripped 16K for a performance rebuild by a reputable rebuilder... when he got it back, it was clear an appi put it back together!

If you decide on the rebuild, make it very(abundantly clear) that all replaced parts are to be kept for you scrutineering... else the odd "refurbished" piston may well find it's way back into the engine... unbeknowns to you!

[Willied]

Going to be doing the build myself.. I will be the only one to blame if old parts are put back.. Hoping to get it running properly and then might even sell it on to fit a 3RZ..

[fredster]

kyk ou maat - Daai 4y's se sukses le in die feit dat hulle so min krag maak - Daar is net nie genoeg torque om die wiele te veel los te breek nie. Om met n groter enjin dieselfde te vermag kos baie geduld en n mooi opgeleide petrol voet.

Die pryse lyk maar hoog vir die parte aangesien die fong kong's so goedkoop is. Indien jy die motor gaan verkoop, sou ek voorstel dat jy nie die duur Toyota parte gebruik om dit te herstel nie - Dit was n fongkong waarmee jy begin het, so jy sal bitter moeilik jou geld terug verhaal. Ek sou aanraai dat indien daar geen merke op die op die silinders is nie en indien daar minimum speling op die pistons is, dat jy slegs die ringe en bearings vervang, en dan die spulletjie aanmekaar sit. En hier kan jy maar die ACL/generic goete gebruik. Dit sal hou tot jou budget reg is vir daai transplant.

[Willied]

Fredster, ek het 'n paar emails gestuur en dit lyk of ek moontlik 'n 3RZ vir 'n goeie prys kan kry.. Dan sal ek die 4Y trek en hom ordentlik regmaak sodat ek hom met 'n skoon gemoed kan verkoop. Sal hopelik maklik 'n huis kry vir 'n 4YE hier op die forum. Maar ek moet eerlik se my kop is redelik opgemaak oor die 3RZ. Dit is net die beter opsie vir my.