Examining a 1961 MK2 Engine
#1
Examining a 1961 MK2 Engine
Evening all -
As you may know, I already have a 1965 MK2....but (and this is a secret, because some people get really bent out of shape over it) my car doesn't have its Jaguar engine or transmission. It came that way, was too hacked up to put back, so I just improved on the existing condition - enough said. However, I've always wanted to have an older Jaguar with the original equipment and I have the opportunity to look at a '61 Mk2 with the 3.8 engine, automatic transmission. The car is supposedly in reasonable condition, but has not been on the road nor in regular use for many years and the current owner does not appear to have much knowledge or history beyond the last 2 years. The car does run, and I'm told it will drive, though likely needs a few things before being strictly road-worthy. I'm familiar with most MK2 systems, but obviously the the engine and transmission are new to me, and I thought I'd ask your advice on tips and techniques for assessing engine health on a car I likely wont be able to test drive.
My initial thoughts are as follows:
Compression test, dry and wet. What sort of compression is typical? Any idea what numbers I should look for and does the 10% +/- difference between cylinders still hold as the red flag for the XK motor, as it generally does for the venerable small block Chevy?
Oil pressure - what is typical here?
Smoke and such from the exhaust - Does the XK give you indications of health from its exhaust? For example, a puff of smoke on start-up, if a small block Chevy, but otherwise no smoke, often means valve guides are worn, more smoke, more worn out. Does the XK 3.8 have similar tell-tale signs to look for?
How about vacuum readings - what is typical for the 3.8? and...where would I connect a vacuum gauge to full vacuum?
Any common issues that can be detected in a static run - i.e. engine is running but no drive test?
Anything else you can think of? The whole point of getting this other car will be to have the Jaguar engine and transmission, so I'd like to have some way of assessing at least the engine's health, given that I won't be able to test drive.
Appreciated,
Allan.
As you may know, I already have a 1965 MK2....but (and this is a secret, because some people get really bent out of shape over it) my car doesn't have its Jaguar engine or transmission. It came that way, was too hacked up to put back, so I just improved on the existing condition - enough said. However, I've always wanted to have an older Jaguar with the original equipment and I have the opportunity to look at a '61 Mk2 with the 3.8 engine, automatic transmission. The car is supposedly in reasonable condition, but has not been on the road nor in regular use for many years and the current owner does not appear to have much knowledge or history beyond the last 2 years. The car does run, and I'm told it will drive, though likely needs a few things before being strictly road-worthy. I'm familiar with most MK2 systems, but obviously the the engine and transmission are new to me, and I thought I'd ask your advice on tips and techniques for assessing engine health on a car I likely wont be able to test drive.
My initial thoughts are as follows:
Compression test, dry and wet. What sort of compression is typical? Any idea what numbers I should look for and does the 10% +/- difference between cylinders still hold as the red flag for the XK motor, as it generally does for the venerable small block Chevy?
Oil pressure - what is typical here?
Smoke and such from the exhaust - Does the XK give you indications of health from its exhaust? For example, a puff of smoke on start-up, if a small block Chevy, but otherwise no smoke, often means valve guides are worn, more smoke, more worn out. Does the XK 3.8 have similar tell-tale signs to look for?
How about vacuum readings - what is typical for the 3.8? and...where would I connect a vacuum gauge to full vacuum?
Any common issues that can be detected in a static run - i.e. engine is running but no drive test?
Anything else you can think of? The whole point of getting this other car will be to have the Jaguar engine and transmission, so I'd like to have some way of assessing at least the engine's health, given that I won't be able to test drive.
Appreciated,
Allan.
Last edited by Treozen; 11-14-2018 at 01:12 AM. Reason: I forget things...
#2
I don't know all the values you are seeking, but if the car is on anything like 100k miles it really needs an overhaul. If the current owner knows nothing about the car then really you should budget for a complete overhaul of the engine and much else besides, as it would appear he didn't really look after it or he'd be only too willing to show you invoices and so on for work done. These cars, like so many of the 60s, are notorious for rusting away, so it is essential this aspect is checked, (unless you're just buying it for the engine and transmission, of course).
#3
If the current owner knows nothing about the car then really you should budget for a complete overhaul of the engine and much else besides, as it would appear he didn't really look after it or he'd be only too willing to show you invoices and so on for work done.
The current owner does not appear to have done anything in the two years he's owned the car, but if the claims are to be relied upon, the owner before him did. As for invoices and records - I can count on one hand, and not use all the fingers, the number of times I've saved a record. I always mean to, but they get lost or I forget, and I've restored, modified, resurrected and ultimately sold many cars over the last 20 years. I view a lack of records as normal, and the presence of them as an unexpected surprise.
No, my '65 has gone too far over to "the dark side" of modification and change to ever again hold the original engine and transmission. If it were feasible, I might consider it, but the car was modified long before I owned it and the modifiers made some interesting choices - some good, some not, and I dare not think of what challenges I might face trying to put the jaguar equipment back in. If all goes well, my '65 will continue to be the faster, more comfortable, and likely more reliable Resto-Mod Mk2, while the '61 will be carefully restored to the best version of original that I can achieve, while doing the work myself.
Last edited by Treozen; 11-15-2018 at 04:43 PM.
#4
Compression needs to be around or over 150psi, oil pressure at least 15-20lbs at idle and 40lbs at 2000rpm and above, but wear in the oil pump can also show low pressure as well as the pressure sender and oil gauge, so you must use an accurate pressure gauge to check this, do not rely on the instrument gauge.
If you can do a leak-by test that will give you much more information than a compression test, if it passes the leak-by test then you know that most things are in reasonable order.
Smoke checks are as per any standard engine, but the leak-by test will also give you most indicators you need.
These engines notoriously leak oil from the rear crank seal, it has a rope seal originally, this can be converted to a proper oil seal, but requires the engine and gearbox out and the crank out to do it, this also applies to the rope seal so if there is oil at the rear of the sump suspect the oil seal is gone, you can live with this and just keep putting oil in it will not effect the engine as such unless the oil gets too low.
Noisy timing chains, this can be worn timing chains, worn timing chain guides, blocked hydraulic tensioner (there is a tiny filter in the block behind it) or just adjustment, leaking core plugs, corroded waterways are also an issue if incorrect or no antifreeze has been used, this results in poor water flow and overheating, check the colour of the water after a run, if it is brownish then the engine would benefit from a good flush through.
The engines themselves are pretty damn good, it is only lack of use or poor maintenance that causes issues. If the engine has done 100K miles or more it would benefit from a rebuild, but if it has been well maintained it would be good for 150K plus, many of these cars were laid up for many years, and it is often that together with poor re-commisioning that leads to failure, usually overheating and a blown head gasket !
If you can do a leak-by test that will give you much more information than a compression test, if it passes the leak-by test then you know that most things are in reasonable order.
Smoke checks are as per any standard engine, but the leak-by test will also give you most indicators you need.
These engines notoriously leak oil from the rear crank seal, it has a rope seal originally, this can be converted to a proper oil seal, but requires the engine and gearbox out and the crank out to do it, this also applies to the rope seal so if there is oil at the rear of the sump suspect the oil seal is gone, you can live with this and just keep putting oil in it will not effect the engine as such unless the oil gets too low.
Noisy timing chains, this can be worn timing chains, worn timing chain guides, blocked hydraulic tensioner (there is a tiny filter in the block behind it) or just adjustment, leaking core plugs, corroded waterways are also an issue if incorrect or no antifreeze has been used, this results in poor water flow and overheating, check the colour of the water after a run, if it is brownish then the engine would benefit from a good flush through.
The engines themselves are pretty damn good, it is only lack of use or poor maintenance that causes issues. If the engine has done 100K miles or more it would benefit from a rebuild, but if it has been well maintained it would be good for 150K plus, many of these cars were laid up for many years, and it is often that together with poor re-commisioning that leads to failure, usually overheating and a blown head gasket !
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Treozen (11-18-2018)
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As you say on initial looks, nothing appears out of place, can you post a pic of it on the ground from the side with a spat off.
Springs maybe weak, you can measure them off the car but that is a bit of work to do right now. It also looks a little high at the front, this could be due to it being low at the rear, but may be a contributing factor to the low rear, a view from the side would be easier to see.
Also check the rubbers in the rear torsion bars, if these are shot the axle will rotate a bit and change the ride height.
See you have a 9:1 compression engine, they are more sensitive to the quality of the fuel, so make sure you use the highest octane best quality fuel you can get at the pumps.
Springs maybe weak, you can measure them off the car but that is a bit of work to do right now. It also looks a little high at the front, this could be due to it being low at the rear, but may be a contributing factor to the low rear, a view from the side would be easier to see.
Also check the rubbers in the rear torsion bars, if these are shot the axle will rotate a bit and change the ride height.
See you have a 9:1 compression engine, they are more sensitive to the quality of the fuel, so make sure you use the highest octane best quality fuel you can get at the pumps.
#16
#17
It would be a good idea to re-build the rear suspension with new poly bushes, at least you know it's all sorted, and you can measure the leaf springs to check if they are potentially weak at the same time.
The compression is changed by the pistons rather than the head, can't think at the moment where the compression is marked on the head if it is at all, they all used the same head as far as I recall.
Why do you think you have a head gasket problem ? These engines do usually take out the head gasket if they overheat too much, common problem is they are not re-commissioned properly as the waterways often silt up giving poor water circulation and hot spots in the system which overheat.
The compression is changed by the pistons rather than the head, can't think at the moment where the compression is marked on the head if it is at all, they all used the same head as far as I recall.
Why do you think you have a head gasket problem ? These engines do usually take out the head gasket if they overheat too much, common problem is they are not re-commissioned properly as the waterways often silt up giving poor water circulation and hot spots in the system which overheat.
#18
#19
Why do you think you have a head gasket problem ? These engines do usually take out the head gasket if they overheat too much, common problem is they are not re-commissioned properly as the waterways often silt up giving poor water circulation and hot spots in the system which overheat.
I did run a compression test, expecting to find a low cylinder or two, but the readings were oddly consistent, and good. 160, 160, 160, 163, 160, 165 - front to back.
I also noted what I believe is piston slap.....sigh.....still, could be worse. Its most noticeable at cold start, gets progressively "better" and once warmed to operating temp, only detectable with your head over the block. In the video below, recorded shortly after start, it is most noticeable at 0.26
All dry, very sooty, consistent condition.
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