406oc.co.uk

I'm sure this has been asked before, but will a RHY go in to a RHZ?

Will what exactly go into what?

I have a 2004 406 110 HDI and we think it has dropped a valve due to a loud banging when running and when the guy up at the garage put the car in the air he said it was loud through the intercooler pipe!

I have a 90 HDI complete from a 1999 V sat in the garage and I just wanted to know if it will go in to my 110.

Dropped a valve? that's weird.

The two engine blocks are the same but there's a lot of differences between the 90 and 110 but maybe you can bolt all your 110 ancillaries onto the 90's block? I don't know if they are the same compression ratio though anyone?....

As far as I know they're pretty much the same engine, except the RHY lacks the intercooler and dual mess flywheel.

Hold on, I can do some comparisons because I have a few VINs hanging about.

Ok then, car A is a 1999 RHY (RPO 8912), car B is a 2003 RHZ (RPO 9891)

A; B

Block (& new pistons) - 0130 T7; 0130 T7
Crank - 0501 K7; 0501 K7
Conrod (& Piston x4) - 0628 N3; 0628 N3
Cylinder head - 0200 GN; 0200 GN
Exhaust Valve - 0949 96; 0949 96
Inlet valve - 0948 95; 0948 95
Camshaft - 0801 T5; 0801 T5

Can anyone think of anything else I should check?

99% sure the compression ratios are different, (though not by much), but this does imply there is somehing else different for that to be possible.

The ecu's won't be comaptible - one's got the wherewithall to control the turbo boost and proabably an air doser and is for a full-mux system, the other has none of these. Suspect this is a bigger issue than owt mechanical.

The camshaft is timed slightly differently? Burgered if I know, you sure you're not thinking 2.0/2.2?

The OP will have to change everything over, wiring loom, flywheel etc. but I don't think the RHZ has much different in the way of sensors - anyone?

Welly wrote:Dropped a valve? that's weird.

Depends what broke, I've seen two damaged engines recently, one was an ever-so-reliable VW Passat that had dropped a valve seat (nasty, even stripped out the piston rings) and the other was a fairly modern Alfa that had a valve break (hammer, hammer, hammer, valve head ended up embedded in the piston crown, what a mess)

i would have a check of the rocker arms as that could go with a bang and be loud from the inter cooler pipe

steve_earwig wrote:The camshaft is timed slightly differently? Burgered if I know, you sure you're not thinking 2.0/2.2?

No, I got it from the tech specs in the handbook, the 2.2's more differenter still

The OP will have to change everything over, wiring loom, flywheel etc. but I don't think the RHZ has much different in the way of sensors - anyone?

AFAIK, RHZ has a MAP sensor, RHY doesn't, that's probably about it, but it's maybe enough that you need to change over the engine loom too. The ecu connectors are different between semi & full mux cars, (one has a single plug, the other has 3), so I think it could be tricky. I'm guessing the OP just wants to swap engines over, leaving all the original ancillaries, which may be OK, but I think you may have to swap the injectors.......

Can you not just change the head? Surely they are the same part as both engines have same cc?

I read somewhere - here probably - that the Hdi engine has weakened rockers which are designed to break before allowing valves to smash into the pistons. As MMM says, maybe check rockers first.

[quote="GingerMagic"]Can you not just change the head? Surely they are the same part as both engines have same cc?

I read somewhere - here probably - that the Hdi engine has weakened rockers which are designed to break before allowing valves to smash into the pistons. As MMM says, maybe check rockers first.[/quote


Well after reading about the rockers I had a thought. Back a good few years ago the guy who used to look after my cars, before he was taken I'll, had a Citroen HDi come in with a broken cam belt. When alen popped the cover off the belt was fine, so he then went for the rocker cover. He found two rockers had broken! With this on mind I calls the garage and told him what had been said on here and what I could remember so he took the rocker cover off and found no2 cylinder, the rocker has come out and is just sat in the well. I've ordered a new rocker from Peugeot so hopefully this should cure it!

That's true if the piston hits the valve at a low enough speed there is a sacrificial breaking in the head, normally though it would be the cam cap which then lets the camshaft lift out the way. Either way it is not always a disaster when the two parts meet.