Talk:Hydraulic tappet

Talk

The following has been moved from the article to here:

This is incorrect as most light vehicle engines in the last 10 years have been made in a Type II configuaration where an overhead cam actuates a Rocker Arm that in turn actuates a valve with the opposite rocker side of the rocker arm being supported by the Hyrdraulic lash adjuster element. Major produces of lash adjusters in the USA include Eaton, Delphi and INA, while of the three INA has the best explanations and models on their web site. Hydraulic lifters were first put into engines, in mass production, in the 1950's by General Motors. Since then Hyrdraulic Lifters have always been a mainstay in domestic engines. In other parts of the world where smaller engines are utilized the tendency was to stick with direct acting tappets however, again, in the past five to ten years the trend is changing towards hydraulic lifters (especially with Toyota). Only Ford is now considerding reverting back to the primitive Type I, direct acting technology but this is because they are desperate to take cost out of their engines in an ill fated attempt to regain profitability; their quality will suffer and consequently so will their market share.

To truly do justification to the history of the Hydraulic Lifter a person could write a 100 page technical paper easily. The person who wrote the above doesn't have accurate information about the topic and should not be allowed to write any more articles. Thanks.

I am an Engineer who works for one of the aforementioned producers and have been working in the design and production of Hyrdraulic Lifters for the past 15 years. It bothers me to see such inaccurate information on Wikipedia, an informaiton source that is becoming highly used by any and everybody.

Flagged for cleanup due to conversational tone and lack of citations. Also, two of the external citation links don't support the material, being links to top-level pages of valve system manufacturers, and I removed them to here. Also cleaned up the formatting of the remaining reference link and some awkward sentence structure. Last paragraph had conversational-tone phrases removed. Lots of material without citations that is probably verifiable, but need 3rd-party references. Page would likely benefit from a rewrite by a subject matter expert.

Removed Links:

• http://www.eaton.com/EatonCom/Markets/Automotive/EngineAirManagement/ValvesLiftersValveAcuation/index.htm
• http://www.ina.com/content.ina.de/en/branches/automotive/engine_systems/index.jsp

Edit: Apologies for not giving an edit summary for submitted changes. Too fast on the Save Page button, I'm afraid. RobAtSGH 18:35, 14 May 2007 (UTC)

Valve closing completely -- I was under the impression that the exhaust valve was supposed to close completely to allow thermal transfer from the valve to the head in order to allow the valve to cool & not burn up. Is this guy nuts? 129.53.219.20 13:26, 12 July 2007 (UTC)

I broke the article in to sections, fixed some bad form, removed the double spaces at the end of the sentences, and I removed the junior-high-essay style "in conclusion" paragraph at the bottom. I know little about the subject at hand, so I invite someone more knowledgeable to clean up the technical aspects.Sofar 2 07:29, 19 August 2007 (UTC)

~ ~ ~ ~ I am not tehnically very literate but was a bit surprised by the article because I was under the impression that hydraulic had become almost universal for reasons of low maintenance of OHC engines in poor environments. The Ford comment seems plausible as I have read several times about their also doubting the desirability of independent rear suspension, due to its greater cost. —Preceding unsigned comment added by 92.8.220.42 (talk) 10:13, 21 July 2009 (UTC)

If anyone wamts to own the edit, I noticed a slight problem. The article declares lifter pump-up a myth, and then goes into fine detail into how lifter pump-up occurs... 50.142.191.253 (talk) 23:56, 12 January 2013 (UTC)

Desmodromic?

Are there any desmodromic engines that use hydraulic tappets ? 82.132.217.120 (talk) 16:21, 21 August 2014 (UTC)

Clearer explanation of how device works to achieve benefits is needed

From reading the article, I cannot clearly understand how the hydraulic tappet causes better valve opening and closing over a solid tappet. If you understand this and can clearly explain it, then go ahead and do so. Don't be overly concerned about personal research and citations, getting a clear explanation is far more important. These people who make the accusation of personal research and insufficient citations with templates are usually people who don't have any concern about the clarity and usefulness of the article. These templates are more often than not just so somebody can pretend they have done something useful. RHB100 (talk) 20:29, 5 May 2016 (UTC)

Solid lifters?

Almost every car on the road has hydraulic lifters?

Popular in the 80's?

Leave engine tech to actual mechanics please — Preceding unsigned comment added by 204.238.236.130 (talk) 14:23, 7 August 2017 (UTC)