Diesel timing query

This may be a bit of an odd one, I know usually when timing up an engine, the timing marks should line up when piston number 1 is at top dead centre, correct?

However,
On my 2.5 diesel the timing marks line up when all 4 pistons are at the middle of the bore. Now is this correct on this engine or do we need to sort this out properly (i.e. timing it when piston is at tdc)? It did run fine which is why we found it unusual for it to be timed like that.

What 2.5 diesel is this?

samc88 said:

This may be a bit of an odd one, I know usually when timing up an engine, the timing marks should line up when piston number 1 is at top dead centre, correct?

However,
On my 2.5 diesel the timing marks line up when all 4 pistons are at the middle of the bore. Now is this correct on this engine or do we need to sort this out properly (i.e. timing it when piston is at tdc)? It did run fine which is why we found it unusual for it to be timed like that.

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on injection pulley there is normally a f and dot use the dot unless frieght rover 2.5 with tin front cover.timing is done at exhaust peak 108 degrees btdc so pistons no1 and no4 arent at tdc

rangy35 said:

What 2.5 diesel is this?

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2.5 N/A land rover engine

jamesmartin said:

on injection pulley there is normally a f and dot use the dot unless frieght rover 2.5 with tin front cover.timing is done at exhaust peak 108 degrees btdc so pistons no1 and no4 arent at tdc

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Ah okay, thank you James Thats cleared that up, cheers

jamesmartin said:

on injection pulley there is normally a f and dot use the dot unless frieght rover 2.5 with tin front cover.timing is done at exhaust peak 108 degrees btdc so pistons no1 and no4 arent at tdc

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Hi James,

I am very new to mechanics so please forgive my ignorance and incompetence!!

I have 1991 12J engine in my ex MOD defender. A week after buying the defender it broke down (it's a Land Rover so I was expecting it to at some point!). After some Haynes manual engine stripping I figured out it was the water pump. Whilst replacing this I got over confident and decided to replace the timing belt.

My method for replacing the timing belt was to literally remove the exiting intact belt and without moving anything replace with a new belt. Needless to say this did not work. The defender turned over and sounded close to firing but never managed it.

I decided to strip it down again and having done much more research, inspect the timing. At TDC none of my dots on the cogs lined up. Thinking that this was the problem i lined them all up. When i turned it over i got the sickening 'clonk' which told me it was not right.

Knowing when to admit defeat i then took it to a specialist 4x4 mechanic. Yes, I had bent the push rods which were replaced, however they too could not get the timing marks right. They were telling me that no1 cylinder needed to be at TDC and then the cog dots should be aligned (which is what i did) but they agreed it was not right and could not figure out what had gone on with the engine.

Since then I have restored the Land Rover and it looks great but it still does not run so I'm really interested in your post where you say 'timing is done at exhaust peak 108 degrees btdc so pistons no1 and no4 arent at tdc'. Sadly i don't understand what this means or how i put my engine into this position to align the cog dots. Are you able to point me in the direction of a post that will explain this further?

Thanks in advance.

PS Sam - your picture heavy posts to this forum have been sooooo helpful to me, my thanks to you too.

engine is timed at 108 btdc there a dot on the crank pulley that should align also pin will fit in rear housing,dot on cam will align with its arrow as will dot on pump pulley

jamesmartin said:

engine is timed at 108 btdc there a dot on the crank pulley that should align also pin will fit in rear housing,dot on cam will align with its arrow as will dot on pump pulley

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Thanks James.

Again sorry for being thick but I think that you are saying that regardless of the actual engine position, if the crank dot lines up with its arrow then the cam and pump should also be aligned? This makes perfect sense and is exactly how i put it together when i bent the push rods. The crank pulley can only go on one way. The pump pulley will move easily. Do you think that a previous owner could have put on the cam pulley without it being lined up, is this even possible? This is the only reason i can think that the timing alignment marks are not working for me.

The guy at the 4x4 garage said he had never seen this in his 29 years of experience. The annoying thing for me is that I know the engine did run!

In the meantime i'm having great fun in rebuilding an engine i picked up for 21 quid off of ebay - this is teaching me loads.

Thanks again.

Pete136 said:

Thanks James.

Again sorry for being thick but I think that you are saying that regardless of the actual engine position, if the crank dot lines up with its arrow then the cam and pump should also be aligned? This makes perfect sense and is exactly how i put it together when i bent the push rods. The crank pulley can only go on one way. The pump pulley will move easily. Do you think that a previous owner could have put on the cam pulley without it being lined up, is this even possible? This is the only reason i can think that the timing alignment marks are not working for me.

The guy at the 4x4 garage said he had never seen this in his 29 years of experience. The annoying thing for me is that I know the engine did run!

In the meantime i'm having great fun in rebuilding an engine i picked up for 21 quid off of ebay - this is teaching me loads.

Thanks again.

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cam pulley like crank has a key so cant be fitted wrong,when marks are aligned engine wont be at tdc,have you any pics

Was there ever a conclusion to this thread? I have a similar issue and have posted a thread:
Anyone an expert on the 14j/15j, please?

Thanks