350i Starting Problems
Discussion
I would say the cam lobes are gone because the lifters just take up the slack.
You could take the rocker bar off and pull out the pushrods - if they are bent massively that might be another explanation.
It will run on 7 cylinders but sounds like you only have 5 (and that's if the other 4 are OK, it might be less...)
You could take the rocker bar off and pull out the pushrods - if they are bent massively that might be another explanation.
It will run on 7 cylinders but sounds like you only have 5 (and that's if the other 4 are OK, it might be less...)
So much for the "reconditioned" engine it was supposed to have...!
We bought a gauge and did a compression test and it barely registered 2bar / 25psi on any of the cylinders.
We also took off the rocker bar and tried to free it all up a bit and gave the valves a tap to make sure they weren't stuck solid but to no avail. The push rods were all straight so the worn lobe theory would definitely make sense.
We will try and source a replacement engine in the meantime and possibly strip the current one to see if it's worth saving, but it looks like it may take longer than the time we have for Le Mans this year!
We bought a gauge and did a compression test and it barely registered 2bar / 25psi on any of the cylinders.
We also took off the rocker bar and tried to free it all up a bit and gave the valves a tap to make sure they weren't stuck solid but to no avail. The push rods were all straight so the worn lobe theory would definitely make sense.
We will try and source a replacement engine in the meantime and possibly strip the current one to see if it's worth saving, but it looks like it may take longer than the time we have for Le Mans this year!
You could just try putting a new cam in it - you can get landrover ones for about £50, and a set of followers maybe another £40?
You'll need a gasket set too.
Just because the cam is shot it doesn't mean the bottom end is knackered too.
It takes about 10 hours to swap over if it goes smoothly and can be done in the car. You jack up the engine a bit for the cam to clear the nosecone on the way out.
You'll need a gasket set too.
Just because the cam is shot it doesn't mean the bottom end is knackered too.
It takes about 10 hours to swap over if it goes smoothly and can be done in the car. You jack up the engine a bit for the cam to clear the nosecone on the way out.
adam quantrill said:
I would say the cam lobes are gone because the lifters just take up the slack.
You could take the rocker bar off and pull out the pushrods - if they are bent massively that might be another explanation.
It will run on 7 cylinders but sounds like you only have 5 (and that's if the other 4 are OK, it might be less...)
I'd have thought that if the pushrods were that bent they would fall out of the rocker arms/ followers and possibly cause an awful clattery mess...You could take the rocker bar off and pull out the pushrods - if they are bent massively that might be another explanation.
It will run on 7 cylinders but sounds like you only have 5 (and that's if the other 4 are OK, it might be less...)
Back with a bit of an update tonight.
I spent a few hours taking off the inlet manifold etc. to get a good look at the camshaft and it is indeed rather worn, well I say rather worn... it has absolutely no lobe half way down, it's completely round!!
So camshaft / followers are definitely on the list of things to be replaced. I managed to pick up a set of recently refurbed HRC 2479 heads for £30 too.
It's going to be interesting to see how the cylinders look once the heads are off
I spent a few hours taking off the inlet manifold etc. to get a good look at the camshaft and it is indeed rather worn, well I say rather worn... it has absolutely no lobe half way down, it's completely round!!
So camshaft / followers are definitely on the list of things to be replaced. I managed to pick up a set of recently refurbed HRC 2479 heads for £30 too.
It's going to be interesting to see how the cylinders look once the heads are off
Are the ones towards the back the worse?
Well the heads are optional really. You may open up more worm cans than you strictly need to and you can always do the heads another time.
If you do take them off you may find hard deposits on the piston crowns. I spent ages scraping it off carefully but I now wish I had remembered something I learned years ago. When I was working on my P4 engine I had the head off and the cruddy valves etc were exposed to damp air for a couple of weeks. Well the crud practically dropped off on its own! So my tip is to put some damp kitchen roll on it and leave it for a few days.
Well the heads are optional really. You may open up more worm cans than you strictly need to and you can always do the heads another time.
If you do take them off you may find hard deposits on the piston crowns. I spent ages scraping it off carefully but I now wish I had remembered something I learned years ago. When I was working on my P4 engine I had the head off and the cruddy valves etc were exposed to damp air for a couple of weeks. Well the crud practically dropped off on its own! So my tip is to put some damp kitchen roll on it and leave it for a few days.
Thanks for the tip Adam, will remember that one 
Agreed the heads could be another can of worms, but one of the exhaust stud holes was dodgy and I'd rather not mess with helicoils or having to re-tap and put a bigger bolt in. Appreciate this will mean the use of a composite gasket and follower pre-load may have to be adjusted and air fuel ratio etc.
The missing lobe was on the drivers side in the centre, I will be trying to check there is not an oil starvation problem like a blocked journal, the other possibility I considered is a seized tappet, but I'm not sure how likely that would be?
Agreed the heads could be another can of worms, but one of the exhaust stud holes was dodgy and I'd rather not mess with helicoils or having to re-tap and put a bigger bolt in. Appreciate this will mean the use of a composite gasket and follower pre-load may have to be adjusted and air fuel ratio etc.
The missing lobe was on the drivers side in the centre, I will be trying to check there is not an oil starvation problem like a blocked journal, the other possibility I considered is a seized tappet, but I'm not sure how likely that would be?
I think the oil goes up tho the rocker shafts and then drips down from there (out the side of each rocker) plus when warm generally oily atmosphere. When I had a failure there was a piece of valve oil seal stuck just above the cam lobe, forming a little dam - so no drips.
I guess you could remove the rocker shafts and check the oil is being pumped up by spinning the oil pump up with an electric drill (having taken off the alternator).
I guess you could remove the rocker shafts and check the oil is being pumped up by spinning the oil pump up with an electric drill (having taken off the alternator).
Got the heads off and the camshaft out this evening, bores look pretty good so I'm going to rebuild rather than replace.
The lifters don't seem to want to come out, is this normal or a further sign that things aren't right?
One suprise was the timing chain, there was about 40mm deflection in the chain... I'm guessing that wouldn't have helped the situation either!
The lifters don't seem to want to come out, is this normal or a further sign that things aren't right?
One suprise was the timing chain, there was about 40mm deflection in the chain... I'm guessing that wouldn't have helped the situation either!
lifters should move freely in the bores. they should always be replaced when you change the camshaft anyway.
Also it's can be surprising how well they will still run, with a totally knackered camshaft.
I got a one that was not hardened correctly and wore completely out in under 100 miles, but will still pull very well upto 3k then miss very bad, took a while to checking timing etc, before we pulled the cam, and saw 80% of the lobes missing.
Also it's can be surprising how well they will still run, with a totally knackered camshaft.
I got a one that was not hardened correctly and wore completely out in under 100 miles, but will still pull very well upto 3k then miss very bad, took a while to checking timing etc, before we pulled the cam, and saw 80% of the lobes missing.
Edited by TVRleigh_BBWR on Tuesday 3rd June 21:17
If the bottoms of the lifters have belled out they won't go up. As you are pulling the camshaft anyway get it out (it will be more fiddly getting it past the lifters) and then I think you can drop them out downwards (or so I have heard). Alternatively it might be varnish buildup on the bottoms of the lifters which could be scraped off. But you need to get them out easily to avoid damaging the holes they sit in.
I'm starting to get the feeling you are somewhat of an oracle when it comes to wedges Adam!!
I pushed them high enough to get the camshaft out, but that was as far as most would go, I did think that getting them out by pushing them down looked easier, but I'll have to think of a way of catching them first!
I pushed them high enough to get the camshaft out, but that was as far as most would go, I did think that getting them out by pushing them down looked easier, but I'll have to think of a way of catching them first!
Just to add to your list of things to do, I'd drop the oil, whip the sump off and pull off any main and big-end bearing cap to check the bearing shells. Best case scenario is that all's well and you just need a new sump gasket (plus of course you could poke the cam followers down and they'd be found in the sump when you take it off 
), worst case you'll be looking at a crank regrind and new shells, seals etc.
I took one of my heads off to Helicoil a couple of stripped exhaust threads in 2001 and ended up with an £800 engine rebuild (that was with me doing all the work except grinding crank and reboring cylinders).
The bearing shells should be a nice even mottled grey colour with a few speckles in: if they're scored or burned or you can see the copper backing, your engine is on borrowed time.
), worst case you'll be looking at a crank regrind and new shells, seals etc.I took one of my heads off to Helicoil a couple of stripped exhaust threads in 2001 and ended up with an £800 engine rebuild (that was with me doing all the work except grinding crank and reboring cylinders).
The bearing shells should be a nice even mottled grey colour with a few speckles in: if they're scored or burned or you can see the copper backing, your engine is on borrowed time.
Well in for a penny... thanks for the tip!
I'm leaning towards getting the block out and giving it a thorough clean and degrease as the fresh oil I put in came out like coal tar! Also the areas I can see are caked in a layer of thick black dry oil.
We have now sourced a well fettled Griff 500HC for our trip to Le Mans so we can dismantle at our leisure and not try to rush things
I'm leaning towards getting the block out and giving it a thorough clean and degrease as the fresh oil I put in came out like coal tar! Also the areas I can see are caked in a layer of thick black dry oil.
We have now sourced a well fettled Griff 500HC for our trip to Le Mans so we can dismantle at our leisure and not try to rush things
Benjamico said:
I'm leaning towards getting the block out and giving it a thorough clean and degrease as the fresh oil I put in came out like coal tar! Also the areas I can see are caked in a layer of thick black dry oil.
That isn't a good sign - it's carbonised oil that can be avoided by frequent oil changes. Apart from what you can see, it starts to gum up elsewhere. You need to scrape out as much as possible, the rocker area, valley, and timing cover are favourite hiding places. This is why I change the oil every 3k.
It's been quite a while, but after so many posts helping in the right direction it's time for an update!
Firstly the Griffith 500 was a lot of fun all the way down to Le Mans, unfortunately that was as far as it got!
We broke down upon arrival to the camp site and after digging a pit, checking wiring, borrowing relays from (very kind) fellow owners and about 8 hours help from Brit Assist we couldn't get it going again!
We had it recovered back to Blighty to be diagnosed with a faulty ECU, I opened it up and the printed circuit board had completely melted!
Back to the wedge, more bad news unfortunately, the main bearings and the big end bearings are completely shot. As such it's beyond economical repair.
I have now managed to find a 3.9 engine with all ancillaries, loom and ECU. Following this weekend's fettling the old block is out and the wedge is ready for the transplant.
I'll be back with updates as the work progresses
Firstly the Griffith 500 was a lot of fun all the way down to Le Mans, unfortunately that was as far as it got!
We broke down upon arrival to the camp site and after digging a pit, checking wiring, borrowing relays from (very kind) fellow owners and about 8 hours help from Brit Assist we couldn't get it going again!
We had it recovered back to Blighty to be diagnosed with a faulty ECU, I opened it up and the printed circuit board had completely melted!
Back to the wedge, more bad news unfortunately, the main bearings and the big end bearings are completely shot. As such it's beyond economical repair.
I have now managed to find a 3.9 engine with all ancillaries, loom and ECU. Following this weekend's fettling the old block is out and the wedge is ready for the transplant.
I'll be back with updates as the work progresses
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