Page 1 of 1

Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 11:52
by Asw
Just split the crank case and discovered that a) my camshaft is worn to **** and b) I don’t have hydraulic tappets. I thought CU engines were fitted with them?
The original replacement camshaft claims to be for hydraulic tappets. Does anyone know the difference in the camshaft for non hydraulic, and is it worth the expense of replacing the existing followers?

Re: Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 14:08
by itchyfeet
Sorry I don't know but I have read some engine reconditioners fit solid lifters as they are cheaper

Re: Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 14:13
by bigherb
They where fitted when it was made. Most probably been changed to solid tappets at some time usually due to the cost of replacing hydraulic tappets.
Hydraulic tappet camshafts have a pre lift ramp on the cam lobes as it has to slightly compress the hydraulic tappet before the valve opens.
Up to you what you do, just that solid tappets the valves will need checking and adjusting every 6000 miles.

Re: Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 17:17
by Asw
Thanks for the info. Follow on question, if i reinstate the hydraulic tappets do I need replacement push rods?

Re: Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 19:15
by kevtherev
yes if they have been changed for solid lifters
explained here
http://www.ratwell.com/technical/HydraulicLifters.html" onclick="window.open(this.href);return false;

Re: Should my CU engine have hydraulic tappets?

Posted: 22 Sep 2013, 21:10
by Asw
Good link, many thanks.
So I have rockers and valves springs that are “hydraulic”.
My push rods are non hydraulic in length, but are all steal and look like the hydraulic unit.... that extra 9mm would have caused some headaches!!
Time to load up the credit card :(

Re: Should my CU engine have hydraulic tappets?

Posted: 23 Sep 2013, 09:05
by Asw
Ok… can anyone point me in the direction of some hydraulic pushrods. I have found a company in California but no one in the UK. Just hope they do export!

Re: Should my CU engine have hydraulic tappets?

Posted: 23 Sep 2013, 09:11
by kevtherev
your best bet would be a breaker I would have thought
plenty about