Bent valves?

[Nivlek2525]

Hi all, following on from my piston ring questions I have another issue. I've put everything back together and got the cylinder head back on.

To get a feel for what kind of compression I might get when I run it I turned the engine over by hand with the compression tested on each cylinder. I could get about 70psi on 1, 3 and 4 but struggling to get much at all on 2.  This just happens to be the cylinder with the biggest ring gap so I assumed it was that. I poured some oil down the bore and it's made no difference. So I taped up the inlet and exhaust ports with gaffer tape and turned the engine over again blocking the spark plug hole on each cylinder. Nothing on cylinder 1,3 and 4 again but 2 is blowing the tape off on inlet and exhaust. So I'm leaking from both valves. Head off again, all looks ok. I've taken the valves out they look well ground in. I spent quite a bit of time doing this months ago. So I've put the valves in a drill and when I spin them I think there might be a bit of a wobble suggesting they are bent. So my question is, are there any simple ways to check for bent valves? Why would both be bent? Is there anything else I can check. I'm tempted to bin it an keep an eye out for a unleaded head and crack back on with something else. All help, comments, thought, jokes and funny stories appreciate.

Kelvin.

Edited November 20, 2020 by Nivlek2525

[Jessopia74]

Did you reset the hydraulic followers? Try winding the rockers right off so they are loose when it's off the cam lobe. This will make sure you don't have a slight lift on the cam base. 
To check for bent valves, you gently roll them on a flat surface (hang the valve head over the side) with your fingers, your feel is more sensitive than your eyes. If they are really really minimal, then you can get a machine shop to reface the valve, or replace.

You can also check in the head if you use a thin oil, paraffin etc and take off the followers, turn over and fill the combustion chamber in the head . Each might leak down extremely slow, but if you see it vanish, you know you gave a seating problem. (seating is just the term for a perfect seal, it could still be slightly bent valve).

 

Edited November 20, 2020 by Jessopia74

[Nivlek2525]

Just now, Jessopia74 said:

Did you reset the hydraulic followers? Try winding the rockers right off so they are loose when it's off the cam lobe. This will make sure you don't have a slight lift on the camsgadtTo check for bent valves, you gently roll them on a flat surface (hang the valve head over the side) with your fingers, your feel is more sensitive than your eyes.

You can also check in the head if you use a thin oil, paraffin etc and 

Yep, took the rockers right off so that all valves were totally closed. I'll try that on the valves tomorrow. Thanks.

[Nivlek2525]

12 hours ago, Nivlek2525 said:

Yep, took the rockers right off so that all valves were totally closed. I'll try that on the valves tomorrow. Thanks

Both valves look ok and feel ok when rolled on a flat surface. The actual stem of the valve is straight against a straight edge. I used marker to colour in the contact surfaces of the valves and turned them a few degrees against each other to see where the market was removed. Exhaust looks ok so not sure what the issue is there. Perhaps it needs lapping in again. 

The imlet, not so good. Doesn't remove the marker evenly around the seat. I made a very crude jig up to see if that indicated anything and to me it's obvious the head of the valve isn't square to the stem. See photos. So possibly one bent valve and one needs ground in again?

https://photos.app.goo.gl/nq59HinvR85PqnB67

 

 

Edited November 21, 2020 by Nivlek2525
Error

[cam.in.head]

hi kelvin. ive looked at the photos. quite difficult to see to be 100% sure but it looks like the valve in question( more so than the others?) has an unusual angle on its mating surface anyway. ?

it may just be the way the photos is taken.the valve sealing surface on the head of it looks to be ground very deep and curved. ? maybee it was done sometime in the past if the seats were reground ?   maybee too deep ?  

i can check what a inlet valve should look like and email you a picture if you like but to be honest you may be right.an unleaded  head would be better all round. 

IDEALY you would want a P2 marked head from a late carlton 1985/86 2 litre carb as i assume yours is a carb engine ? 

if not a P2E for injection .  at least that way you get a good head and dint have to mess about finding a trustworthy shop to fit unleaded inserts .the gm ones will be done correctly !

a P2E head will also physically fit and work but you must fit the gte cam and play with the ignition timing. 

( a gte head is basically a skimmed version of a carb head and thus sits fractionally lower so retarding the valve timing slightly so a gte cam has a slightly advanced profile .)( same reason a gte cam will work well in a non injection engine if the chain is not brand new !)

 

[Nivlek2525]

3 hours ago, cam.in.head said:

hi kelvin. ive looked at the photos. quite difficult to see to be 100% sure but it looks like the valve in question( more so than the others?) has an unusual angle on its mating surface anyway. ?

it may just be the way the photos is taken.the valve sealing surface on the head of it looks to be ground very deep and curved. ? maybee it was done sometime in the past if the seats were reground ?   maybee too deep ?  

i can check what a inlet valve should look like and email you a picture if you like but to be honest you may be right.an unleaded  head would be better all round. 

IDEALY you would want a P2 marked head from a late carlton 1985/86 2 litre carb as i assume yours is a carb engine ? 

if not a P2E for injection .  at least that way you get a good head and dint have to mess about finding a trustworthy shop to fit unleaded inserts .the gm ones will be done correctly !

a P2E head will also physically fit and work but you must fit the gte cam and play with the ignition timing. 

( a gte head is basically a skimmed version of a carb head and thus sits fractionally lower so retarding the valve timing slightly so a gte cam has a slightly advanced profile .)( same reason a gte cam will work well in a non injection engine if the chain is not brand new !)

 

Thanks CIH. 

My engine is a GTE and I intend to run it on injection, but you are right, the car would have been carbs. I just bought a full GTE engine, loom, manifolds etc.

I've had another look this afternoon and I'm less convinced the valves are bend and more convinced they aren't seated. When I ground them in originally I noted that the landing width was well over spec. Someone has really gone to town in the past and yes, they were all as bad as each other really. not curved but very wide contact surfaces. This, together with the worn bores and rings I'm inclined to just park it and wait for the right engine to come up. I'm in no rush as I have a ton of bodywork to do and it will be easier to pick something up once this lockdown business is over. I've let it distract me from the main job to be honest.

I'll spend an hour tomorrow grinding them in again and see if I can get a seal. The engine was never going to be great but I hoped I could use it the get the injection set up and check the gearbox, axle etc. 

I paid a £100 for the engine complete with everything down to the ECU so it doesn't owe me anything really and I've enjoyed pulling it apart and doing research. I was just hoping I could get it going for a bit of a shake down of the car when the time comes.

A decent P2E engine or 2.4 frontera engine will turn up next year. I know of one 2.0L where I got some other things from so might be able to get that. 

Again, really appreciate the advice.

Have a good Saturday.

Edited November 21, 2020 by Nivlek2525

[cam.in.head]

no problem . as you say the whole package was cheap enough and gave you the bits you needed. 

for what its worth.if you can seat the valves i would put it all back together and get it running. its all part of the fun and good experience .

have a good weekend yourself . roll on next year !

[Nivlek2525]

26 minutes ago, cam.in.head said:

no problem . as you say the whole package was cheap enough and gave you the bits you needed. 

for what its worth.if you can seat the valves i would put it all back together and get it running. its all part of the fun and good experience .

have a good weekend yourself . roll on next year !

https://photos.app.goo.gl/nwusvTTqnnkLtZsF9

 

Just for info. Thought I'd add a couple of pictures of the valves for reference. The first two are the inlet and exhaust from the GTE engine and the second 2 are from my 2.4 head for comparison. Obviously I've never cleaned up the 2.4 but the inlets look very different, the exhausts look similar actually. 

I bought the 2.4 head ages ago for the aluminium rocker cover as it was one a few quid. I also thought I might be able to do a big valve head by either using the valves or getting the head skimmed down and using a Vernier gear to correct the timing. So far it's donated a couple of retainers which I lost when taking the 2L head apart.😬

Cheers.

[1200bandit]

Roll the valves on glass which should be 100% flat , you see if the valve is distorted 

 

[Jessopia74]

Personally, those valve seats need to have that pitting removed and it looks like that valve is worn beyond what I would consider serviceable. Think you found the issue. 

[Nivlek2525]

40 minutes ago, 1200bandit said:

Roll the valves on glass which should be 100% flat , you see if the valve is distorted 

 

Thanks, I did that on a flat work top. The part of the stem that is the same diameter all the way down is flat/straight, I'm happy with that. I just thought the valve head was off square ever so slightly bit I think I'm seeing things. 

25 minutes ago, Jessopia74 said:

Personally, those valve seats need to have that pitting removed and it looks like that valve is worn beyond what I would consider serviceable. Think you found the issue.

Yes, I think the engine has a lot of miles on it. As I said above, I'll try to seat the valves just to see if I can get it up and running but realistically I was never happy that this was going to be right engine for the car. I've spent a long time getting the car as good as I can get it, I want the engine to be right as well.

 

[Jessopia74]

33 minutes ago, Nivlek2525 said:

Thanks, I did that on a flat work top. The part of the stem that is the same diameter all the way down is flat/straight, I'm happy with that. I just thought the valve head was off square ever so slightly bit I think I'm seeing things. 

Yes, I think the engine has a lot of miles on it. As I said above, I'll try to seat the valves just to see if I can get it up and running but realistically I was never happy that this was going to be right engine for the car. I've spent a long time getting the car as good as I can get it, I want the engine to be right as well.

 

If I am honest, you might consider buying a good used head. Might be cheaper overall

[Nivlek2525]

26 minutes ago, Jessopia74 said:

If I am honest, you might consider buying a good used head. Might be cheaper overall

Yep, but the bores are worn more than I would like so I think another lower mileage unit is the way forward. The only reason I'm still planning to spend any time on it is because its all apart and I'm interested to see what happens. I'll look for a new engine in the new year. There are some decent parts on it to keep as spares so nothing lost really. If I continue to grind the pits out of the current seats there will be no seats left😀.

 

Edited November 21, 2020 by Nivlek2525

[H-400]

Maybe the moment to consider to let the engine bore & hone and fit new oversize pistons. I payed 300€ for the work in an overhauling firm. The new pistons & rings were found on internet for 500€. Had luck cause the crank didn't need any work but fitted new bearings. Than you'v got a new block.

[Nivlek2525]

43 minutes ago, H-400 said:

Maybe the moment to consider to let the engine bore & hone and fit new oversize pistons. I payed 300€ for the work in an overhauling firm. The new pistons & rings were found on internet for 500€. Had luck cause the crank didn't need any work but fitted new bearings. Than you'v got a new block.

Hi Herman, hope you are well.

I've looked at the options and this is just to expensive for me at the moment. The cheapest pistons I can see are about £650 + labour + unleaded head etc etc.

I need to get the car right first. I may get this kind of work done at some point but maybe on a 2.4 rather than a 2 litre. I think a good, proven used item is the right option for me now. But not until.the new year. I need to get on with bodywork, I've let myself get distracted.

Cheers.

K 

[rutts]

This guy has pistons 143642886513 eBay. 

[611]

On 22/11/2020 at 10:19, Nivlek2525 said:

Hi Herman, hope you are well.

I've looked at the options and this is just to expensive for me at the moment. The cheapest pistons I can see are about £650 + labour + unleaded head etc etc.

I need to get the car right first. I may get this kind of work done at some point but maybe on a 2.4 rather than a 2 litre. I think a good, proven used item is the right option for me now. But not until.the new year. I need to get on with bodywork, I've let myself get distracted.

Cheers.

K 

Save a bit more that that if your going to do a 2.4!!

Bored out 2.0L with a big valve head would be a nice option and the cheaper option.

2.4 is a bit more specialist so not as many options for pistons etc.. as the 2.0L

Just my thoughts and experience on the engine side of life.

Andy

[Nivlek2525]

43 minutes ago, rutts said:

This guy has pistons 143642886513 eBay. 

Many thanks. Looks like he only has 3 but shows that everything turns up on eBay eventually.

 

38 minutes ago, 611 said:

Save a bit more that that if your going to do a 2.4!!

Bored out 2.0L with a big valve head would be a nice option and the cheaper option.

2.4 is a bit more specialist so not as many options for pistons etc.. as the 2.0L

Just my thoughts and experience on the engine side of life.

Andy

Cheers, I'm getting the impression 2.4 are expensive to rebuild if they need it. I thought they were just a stroked 2 litre engine but apparently it's not quite that simple. 

I've managed to get the valves to seal on my engine over the weekend so they weren't bent just worn and not properly seated. My error. It's clearly very worn but it will do for now I think. 

I'll explore the options. I did wonder about putting hardened seats in my head but open them up to take the larger frontera valves? I appreciate the head would need some work to take advantage of the bigger valves but might be interesting. 

Focus needs to go back on the car for now. There's still plenty to do there first.

Thanks again 👍

 

[611]

21 minutes ago, Nivlek2525 said:

Many thanks. Looks like he only has 3 but shows that everything turns up on eBay eventually.

 

Cheers, I'm getting the impression 2.4 are expensive to rebuild if they need it. I thought they were just a stroked 2 litre engine but apparently it's not quite that simple. 

I've managed to get the valves to seal on my engine over the weekend so they weren't bent just worn and not properly seated. My error. It's clearly very worn but it will do for now I think. 

I'll explore the options. I did wonder about putting hardened seats in my head but open them up to take the larger frontera valves? I appreciate the head would need some work to take advantage of the bigger valves but might be interesting. 

Focus needs to go back on the car for now. There's still plenty to do there first.

Thanks again 👍

 

The basics are the same apart from a few things that just add up to making it a bit more expensive to do. It is a stroked 2.0L, but because of that the piston skits wear as the pistons are much shorter than the 2.0L so any engine you get will likely need a rebore and new pistons before you do anything else. Mine was 70K mileage. Pistons skirts all scuffed, so new pistons needed (i could get originals which were cheaper, but i think long term i should of gone for the Woosner with coated skirts. £650+ needed a rebore as noticeable ridge, so that's more money. Intakes on the head are higher so different inlets needed for carbs, special thermostat as that is different than the 2.0L. Dipstick hole need moving as in the wrong place for steel sump. You need a decent a decent cam to extract the power from it, more money, just seems to keep adding up.

And you need to buy the 2.4 in the first place!! 

If you have a good block i would look at seeing what you can do with that as its just pistons, valves and some engine work. Had a friend who had a 2.0L bored out to probably 2.3, big valve head, nice cam and that shifted 🙂 

Worth weighing it all up before you head down one route as once you start its hard to go back.

Got a far bit of stuff on my rebuild if your bored in lockdown http://theopelproject.com and loads of good engine advice on the GT forum https://www.opelgt.com/

 

Andy

[Jessopia74]

As above, absolutely nothing wrong with building a 2.4 bottom end based on a 2.0 block.

[H-400]

Drove years with a 2.4 and just rebuilded it (see "swan neck"). I am sure the cast iron of a 2 liter is better (harder) than the 2.4 block. And i'm not the only one with that opinion. Noticed also before boring & honing my 2.4block the pistons were rocking (is this the right defenition in English?). The engine made a sound at idle as there was a hydraulic tappet with too much clearance. It was hard to notice but we are all petroll heads so I do also listen to my engine. When I reved up only a bit the sound was away... So the skirts were worn and the sides (L & R) of the cilinder was polished and oval.

Fitted again a 2 liter head because I want to flow the 2.2 head and that shortened 6 cil inlet. The 2.4 runs nice and has got a nice torque, doesn't knock and it's gonna be that way for a while. Got to open the engine of the "400" 

@Kelvin: The knee is getting better, but no "Iron man" stuf 😄 

[Jessopia74]

1 hour ago, H-400 said:

Drove years with a 2.4 and just rebuilded it (see "swan neck"). I am sure the cast iron of a 2 liter is better (harder) than the 2.4 block. And i'm not the only one with that opinion. Noticed also before boring & honing my 2.4block the pistons were rocking (is this the right defenition in English?). The engine made a sound at idle as there was a hydraulic tappet with too much clearance. It was hard to notice but we are all petroll heads so I do also listen to my engine. When I reved up only a bit the sound was away... So the skirts were worn and the sides (L & R) of the cilinder was polished and oval.

Fitted again a 2 liter head because I want to flow the 2.2 head and that shortened 6 cil inlet. The 2.4 runs nice and has got a nice torque, doesn't knock and it's gonna be that way for a while. Got to open the engine of the "400" 

@Kelvin: The knee is getting better, but no "Iron man" stuf 😄 

Piston slap is what you describe Herman. Especially when cold, however the old boys that used to rally MK2 escorts used to have this issue on thier 2.1pinto engines as they used to slightly overbore for extra clearance to allow for more heat expansion in the pistons. Sounded counter productive to me back then as it did promote oval wearing. But they seemed to do very well  😎

 

[611]

7 hours ago, Jessopia74 said:

Piston slap is what you describe Herman. Especially when cold, however the old boys that used to rally MK2 escorts used to have this issue on thier 2.1pinto engines as they used to slightly overbore for extra clearance to allow for more heat expansion in the pistons. Sounded counter productive to me back then as it did promote oval wearing. But they seemed to do very well  😎

 

My mate had a cortina with a 2.1 pinto in it and didn't have it over bored and it did use to seize when it got very hot when the engine was first rebuilt. He use to keep it running at the garage when he fuelled up as if he switched it off we would have to wait 30 mins for it to cool down before it would start again!! After a few months it wore itself in enough to be ok, was always a bit of fun going out in it with him 🙂 

[Jessopia74]

3 hours ago, 611 said:

My mate had a cortina with a 2.1 pinto in it and didn't have it over bored and it did use to seize when it got very hot when the engine was first rebuilt. He use to keep it running at the garage when he fuelled up as if he switched it off we would have to wait 30 mins for it to cool down before it would start again!! After a few months it wore itself in enough to be ok, was always a bit of fun going out in it with him 🙂 

Ah 👍 so there was something in that madness after all. All these years never really understood the reason, now I know ty.

[Nivlek2525]

13 hours ago, H-400 said:

Drove years with a 2.4 and just rebuilded it (see "swan neck"). I am sure the cast iron of a 2 liter is better (harder) than the 2.4 block. And i'm not the only one with that opinion. Noticed also before boring & honing my 2.4block the pistons were rocking (is this the right defenition in English?). The engine made a sound at idle as there was a hydraulic tappet with too much clearance. It was hard to notice but we are all petroll heads so I do also listen to my engine. When I reved up only a bit the sound was away... So the skirts were worn and the sides (L & R) of the cilinder was polished and oval.

Fitted again a 2 liter head because I want to flow the 2.2 head and that shortened 6 cil inlet. The 2.4 runs nice and has got a nice torque, doesn't knock and it's gonna be that way for a while. Got to open the engine of the "400" 

@Kelvin: The knee is getting better, but no "Iron man" stuf 😄 

Pleased you are on the mend Herman. Take it easy though.

The more I read the more options I realise there are...