Jowett Javelin Restoration (Spain)

[Moises Jr.]

Hi all.

This is the vision of Jowett Javelin cylinder heads exposed working

http://www.youtube.com/watch?v=hf7JLRLB05s

[Moises]

The cylinder compression is already 130 p.s.i. in each cylinder

[Forumadmin]

Thanks for the video. I did not hear it backfiring or the valves bouncing. The valve noise does not seem normal but that may be the microphone. My initial guess is petrol starvation causes the dying, but it is a guess as I cannot relate the sound to the accelerator depression.

[Moises Jr.]

Hi Keith

Explosions are constant keeping the accelerator, and seem to occur in the carburetors. I'm not an expert, but if explosions occur out of place, could be due to poor closure of the valves that leaks detonation?.

When test drive, powerful engine is not shown, although it is also true that I do not have to compare it, but my father says that the car was much more powerful.

I can think of so many years driving modern cars with 6 cylinders helps to forget the virtues of a Javelin. He is convinced that it does not work really well.

Thanks!

Un saludo!

[Moises]

I have tested cylinder compression. With the engine hot (75 ºC) the compression is: 130,135, 130 and 130 p.s.i. I have introduced a small amount of oil into each cylinder.The readings, then increased to 160 psi in each cylinder. Can piston rings be spoiled?

[Forumadmin]

If it is a new engine which has not run a lot , it may be that the rings have yet to bed in.The cranking speed can make a lot of difference to the compression obtained. If the rings are not correct I would expect to see smoke out of the exhaust and also exhaust gas coming out of the oil filler tube when filer cap is off.

I would expect 160 to 180 psi if the heads have been shaved to get higher compression.

I do not think the problem is compression as all cylinders are the same (although the difference obtained with oil is surprising.) Just to be sure, run the engine again (to clear out any oil) and test compression again without adding oil to cylinder.

If you turn the engine over slowly by hand (with spark plugs in, but ignition off) you might be able to hear where the air is going out at TDC, either inside the crankcase, up through the carb or down the exhaust. It could also tell you which cylinder is the problem. Normal expulsion of air at slow crank speeds should not be heard, it is only a leak on the compressing cylinder which will 'shush'.

Did you do the test with all spark plugs out?

I guess what we really need for a comparison are some perfomance figures. Say 30 - 50 mph acceleration times in top gear or even top speed. Sorry not in kph but most Javelin statistics will be in mph. I would expect a Jav to do 80mph in top gear on the flat with no wind but might be satisfied with 70mph (120 kph). If you can only make it to 100 kph then that might be acceptable for town use, but I expect the fuel economy would be poor and so we should fix it. I have posted dynomometer curves of my engine but unless you have a friendly facility it would be expensive just for this test. Obviously do not push the car if it does not sound happy or has still to run in, but a 50 to 80 kph acceleration time could be used for comparison even on a new engine.

[Moises]

Thank you Keith. I have repeated the test compression as you say: With the spark plugs out and throttle wide open, the readings are 130 psi for each cylinder.
I have tested the vacuum by connecting a vacuum gauge to the vacuum breather pipe. With the engine running at 900 rpm. the depression in the inlet manifold is 17 ins.Hg. When accelerating the engine the reading drop to 0 and return to 19 when decelerating. I think that this readings indicates worn piston rings.
Madrid is 650 m. altitude and atmospheric pressure during the test was 27.28 ins.Hg. (29,57 sea level). This should be taken into consideration when the results of the test are examined.
Do you think I should remove cylinder heads and pistons and examine valves, fit a set of double spring valves and change piston rings?

[Moises Jr.]

Hi All.

Show a link to a video of Javelin this same weekend running

http://youtu.be/Rv8LPVCNSBM

Saludos!

[Moises Jr.]

New pictures about Javelin restoration

http://flic.kr/s/aHsjvNkMRV

[Moises Jr.]

New photos on the work of upholstery
http://flic.kr/s/aHsjvNkMRV

Saludos!

[Moises Jr.]

New photos of upholstery, panoramic viewer.

[Forumadmin]

For a moment I thought Dad had bent the car!

[Moises Jr.]

Is the panoramic effect, the car remains closed pending completion of the roof ... what next is to update the car documents to legally run

[Moises Jr.]

New photos in flickr

https://flic.kr/p/mH2EBM

[Moises Jr.]

Hi all.

The restoration process is practically finished. Amazing picture with high dinamic range effect.

Saludos!