Clatter in pre-x flow engine. 1500 2731E Ford

dikko · 13 Jul 2009, 19:53 (Ref:2501098)

Clatter in pre-x flow engine. 1500 2731E Ford

Changed pistons and renewed cam a while ago (1000 miles) but didn't renew followers (nobody had any at the time thin stem type). Quiet for a while then gradually getting clatter, quiet when cold originally now noisy on start-up, sounds like cam followers, certainly in the cam area.... engine out; followers all good, mmmmm, going to get cam checked for wear. The followers look like they may be hitting the bottom of the block but there's no damage just roughness outside a ring of shine. Could be my imagination though. Perplexed.
Anything else I should have good look at?
Who has steel ones if I should go that way?

Al Weyman · 14 Jul 2009, 07:47 (Ref:2501381)

Putting 2nd hand followers in with a new cam has to be a no, no surely. I do in my engines but only because I use roller followers so you can mix and match no problem but with a flat tappet cam no way I would suggest you have now wiped out the cam and will have to fit a new set of followers and a cam and run it in very carefully for 20 minutes at about 1500 to 2000 rpm after starting and liberally coat it with cam assembly grease when assembling. The cam to follower contact area is the most wear prone on the engine, think for a moment what it is doing.

dikko · 14 Jul 2009, 08:59 (Ref:2501409)

wise words...I'm sure you are correct in your knackered cam assumption. Will let you know....

GORDON STREETER · 15 Jul 2009, 10:25 (Ref:2502132)

When you say "thin stem" do you mean stem or follower diameter ? as I thought the 273 series blocks had the bigger bore anyway. If not the block can be reamed out to suit.
There were 3 types of follower in the Ford Kent series, and if fitting the later bigger dia stem and follower you will have to relieve the area around the follower base on some blocks. This sounds like your problem.

Al Weyman · 15 Jul 2009, 12:16 (Ref:2502186)

Ther you go, words of true wisdom from the expert!

GORDON STREETER · 15 Jul 2009, 13:07 (Ref:2502212)

Don't big me up too much Al otherwise I won't get out of the door !
Anyway as you rightly said old cam followers on a new cam !!! I don't expect its got any lobes left

GORDON STREETER · 15 Jul 2009, 13:11 (Ref:2502216)

dikko the 3 types were a thin dia stem with a small dia head, thin stem larger head, then larger dia stem and head. I don't think you can get the first type anymore.
The first type used to snap off and break the block if they weren't given decent oil and were out of adjustment.

JamesH · 16 Jul 2009, 09:26 (Ref:2502649)

Would like some thoughts...

I have a few sets of 2nd hand XFlow follower that are dished, and I have ground them down very carefully to balance them and get rid of the dishing, then lapped them to a very flat finish. They are pretty accurate (micrometer measured to ensure face is at right angles to the stem).

Is that an valid thing to do or is it really not worth it? I reckon that lighter followers should retain a bit more power (tried working out how much, but its quite an awkward calculation)

Not yet built the engine...

terence · 16 Jul 2009, 11:38 (Ref:2502709)

I would have thought that you could have negated the case hardening Jame's, no doubt Gordon will put you right though.

JamesH · 16 Jul 2009, 12:23 (Ref:2502728)

I was quite careful not to get them too hot - short bursts, hand held so I knew the heat, and I didn't go any further than the bottom of the dishing, but you could be right. I await Gordon's verdict!

How deep are they hardened (if indeed they are hardened)?

Al Weyman · 16 Jul 2009, 12:52 (Ref:2502746)

They aint meant to be flat James but convex!!!! Thats what keeps them rotating and stopping the cam going walkies at least thats what I have always read.

JamesH · 16 Jul 2009, 13:35 (Ref:2502773)

Yes, I know, but I had a brand new set of followers with a new Kent cam, and they were flat as a pancake....

Anyway, flat has to be better than concave...which is what they wear to...hasn't it??

Edit: Just realised, what I meant by dishing in the above comments is that they had worn to concave from the original convex.

St Eval · 16 Jul 2009, 15:28 (Ref:2502823)

I always thought that they were meant to be flat, and the cam rotated them by running fractionally off centre, maybe wrong. Definately no good resurfacing them, case (surface) hardening will be gone.

GORDON STREETER · 16 Jul 2009, 16:20 (Ref:2502848)

Always use new ones ! What's the sense in using old ones ? They are one of the most stressed things in the engine and in the big picture cost sod all.
And yes they are convex but only very little.

redturner37 · 16 Jul 2009, 18:53 (Ref:2502932)

Quote:

Originally Posted by St Eval

I always thought that they were meant to be flat, and the cam rotated them by running fractionally off centre, maybe wrong. Definately no good resurfacing them, case (surface) hardening will be gone.

Absolutely correct, and for what they cost, bin the lot.

dikko · 16 Jul 2009, 18:54 (Ref:2502933)

Er, followers are the thin but heads are quite large....I'll measure....

However! There's nuthin wrong with them! Cam is good too... Whatsmyclatter?

I've sent the rods and pistons to be looked at in case I've run the small ends for some reason...oil holes all OK...and will find out soon if they are to blame...(what do small end wear sound like?) if they're not to blame what the hell was making the din? Pistons look good, etc.

....new followers on order. I could get me file out and make sure the old ones are OK

GORDON STREETER · 16 Jul 2009, 22:51 (Ref:2503047)

You say that you renewed the camshaft. Did you replace it with the same type and lift ? As I said the cam followers can touch the block, also the push rods do rub on the side of the cylinder head if you have more lift as the rocker rotation pulls it over further.
These engines are one of the easiest to work on and loads of posters (including me) have been tuning these engines for the last 40 + years.
I've seen it all including one guy that had a rattle after fitting a big valve head. What he hadn't done was to realise the valves were "too big" and as the head was designed for an 85 mm bore they were hitting the block !
Without looking at the engine its like asking how long a piece of string is I'm afraid

JamesH · 17 Jul 2009, 10:02 (Ref:2503200)

Quote:

Originally Posted by redturner37

Absolutely correct, and for what they cost, bin the lot.

I have heard of one crossflow engine builder (very successful too) who reduces down (new) followers to reduce reciprocating mass....

Staying on the subject of case hardening, almost every Xflow I have stripped has had followers that have worn to concave. presumably all the case hardening has worn away on these, and yet they still run fine. What's that all about? Presumably they would wear faster, but on a race engine that is frequently stripped is that a problem?

Are followers actually case hardened anyway, or is it just the cam? Finding it difficult to get a specific answer from Google.

JamesH · 17 Jul 2009, 10:04 (Ref:2503201)

Quote:

Originally Posted by GORDON STREETER

I've seen it all including one guy that had a rattle after fitting a big valve head. What he hadn't done was to realise the valves were "too big" and as the head was designed for an 85 mm bore they were hitting the block !

Ouch. That's gonna smart.

GORDON STREETER · 17 Jul 2009, 15:38 (Ref:2503356)

For the disbelievers this is from the Kent Cams Manual

dikko · 17 Jul 2009, 17:43 (Ref:2503427)

"You say that you renewed the camshaft. Did you replace it with the same type and lift ? As I said the cam followers can touch the block, also the push rods do rub on the side of the cylinder head if you have more lift as the rocker rotation pulls it over further." Gordon.

Same cam, (Kent 244) previous was as quiet as a mouse...new followers ordered, Ill make sure of clearances as I put them in, the noise was coming from that area so somehow what you say could be the source, don't know how...maybe the pushrods/rockers have moved. Ugh... thanks for helping out...am I getting closer to the mystery I wonder.

JamesH · 20 Jul 2009, 07:33 (Ref:2504630)

Quote:

Originally Posted by GORDON STREETER

For the disbelievers this is from the Kent Cams Manual

Doesn't explain why the last set of Xflow followers I got from Kent were flat then....!!! (Locost spec Cam which is pretty much a GT)

GORDON STREETER · 20 Jul 2009, 08:44 (Ref:2504668)

Quote:

Originally Posted by JamesH

Doesn't explain why the last set of Xflow followers I got from Kent were flat then....!!! (Locost spec Cam which is pretty much a GT)

James, When you get a new set of followers put one in an accurate lathe and check with a dial gauge as we are not talking about a large amount. The picture is exaggerated for the illustrated article.

JamesH · 20 Jul 2009, 15:34 (Ref:2504928)

Quote:

Originally Posted by GORDON STREETER

James, When you get a new set of followers put one in an accurate lathe and check with a dial gauge as we are not talking about a large amount. The picture is exaggerated for the illustrated article.

Will do. I'm quite intrigued. Not sure my lathe will be that accurate, but I'll give it a go!

VIVA GT · 20 Jul 2009, 15:48 (Ref:2504938)

I would have thought that a simple check with a straight edge held up against the light should be sufficient. Alternatively try standing them on a flat plate, if they can be rocked from side to side (when 'sitting' on the follower face) they're convex, if not they're either flat or concave.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Increasing Hyabusa CC to 1500	jhawkins	Racing Technology	5	15 May 2005 10:00
Engine problems at Ford...	fast95pony	Road Car Forum	1	14 Sep 2004 19:44
Ford Kent Engine parts	mattray	National & International Single Seaters	5	29 Nov 2003 09:17
F3 teams dump Ford engine	Super Tourer	National & International Single Seaters	6	22 Apr 2002 12:53