22 replies to this topic

[ckendall]

Hi all can anyone help me out on this one ???

I have a 1330 engine that i bought second hand. I cleaned it down and put it in and there seemed to be no problems at idle BUT on the way to get the car MOT'ed she wouldn’t go over 45mph and struggled all the way there with a horrible rattling sound

I took it to Southam mini and metro centre for the MOT where they set it all up and tried to get her running the best they could but to no avail

Southam said that it could be that one or more of the pistons weren’t sitting in there bores correctly

So now I’ve got her back home and want to check this out to see if it could be that

Can anyone tell me what the clearance should be on a 1330 block ????

If not it looks like it will be going somewhere to be rebuild

[AndyMiniMad.]

Did they do a compression or leakdown test? This is the qiuckest way to check the condition of your engine without having to remove the head.

[ckendall]

A compression test was done cylinder 1 115psi - 2,3 & 4 were 120 psi if that’s any help ???

Could the rattling indicate bottom end bearings gone ???

[AndyMiniMad.]

Thats a bit low on compression right enough....The rattling could be many things and its not worth speculating without hearing it. But it might be a simple case of the valves needing lapped in. But the only way to be sure is to wheek the head off.

[ckendall]

The head has been stripped and cleaned & new valve seals and all the valves lapped in

Thanks for the replys so far

[Ethel]

If you've had the head off you probably would have noticed that much bore wear by the ridge it would leave above the top ring. The pressure figures are fairly constant across the bores too, which is more of an indication of a poor test to me. Think I'd investigate the timing chain before doing anything more drastic.

[skoughi]

Sounds much the same as my 1330 before i took her off the road. I did a comp test as well and got much the same results as you but looking back i did the test wrong. Did it when the engine was cold and if i remember i only took out the plug that i was testing. Mine rattled like mad as well, but when i took of the timing cover the chain was very worn and the tensioner wasn't actually touching the chain! I could move the cam sprocket while the crank one didn't move. I would like to know piston to bore clearence as well as i need to check my bores as well so if anyone on here can help please do!!

[ckendall]

I've been searching the internet for a couple of hours now and by the looks of things on a 1275 to 1330 -- 0.0025in - 0.0032in piston to bore clearance seems to be the figure ??? (Source = 1275cc A-Series High-Performance Manual By Des Hammill)

Can someone confirm this figure ? If this is the case i got a big problem as by the looks of things i could get half of my gauges between the piston and bore

[ckendall]

The comp test was done at Southam mini with all the plugs out and the engine warm

[AndyMiniMad.]

Have you got a picture? What does it say on the top of the pistons? Are you measuring the gap at the top, middle and bottom of the stroke...

[ckendall]

Not had the time to do it (cooking dinner and just about to put kids to bed )

I did take a quick look at the block this afternoon and looking at the figures stated the gap i have is alot bigger

once the kids are in bed i'll try and read the top of the pistons and get a pic up loaded

Thanks to all for the replys

[ckendall]

Not had time to get a pic or read the tops of the pistons sorry

Can anyone shed some light on the figures of 0.0025in - 0.0032in piston to bore clearance ??

[MRA]

Those figures are good enough for a road car, however I really cant see how you would measure them ? the facts are the piston clearance is measured at the skirt and only at right angles to the gudgeon pin.... so its a full strip down to check.

[mini13]

desired bore clearance depends on what pistons you have as different manufacturers pistons will expand different amounts,

also pistons expand more at the crown than lower down so are tapered (and also oval) ey need to measure the piston around 10mm from the bottom at 90 deg to the gudgeon pin, as mad as it sounds its possible to have pistons with .5mm clearance at the crown, however when the crown is at a few hundred degrees they can fit properly.

[ckendall]

Thanks for the replys

So if theres no way of checking it with out a full strip down am i just better off taking the block out the car and sending it back to southam to let them take a look at it OR is there anything else i should be looking at ????